AMC V8 Shenanigans

[TyTheJeepGuy]

I had a perfectly running (at least) twice rebuilt '77 AMC 401. Most recently rebuilt by me (because I let a bolt fall into the intake on a test drive...), so I know all the juicy numbers and exactly what is in it now.

Dyno'd at 250hp (SAE corrected) at the 33" mud tires. Oddly, after adding fiberglass wrapped short tube headers, Holley Sniper EFI and HyperSpark ignition control with a professional tune, crossover x pipe on the exhaust, best dyno run was 249hp... go figure. The late 70s heads just do not flow air past 43-4500 rpm.

After getting maybe 14mpg on highway at best and you can bet more on 11mpg especially if holding 75mph, this didn't sit well with me. I want big power if I have to deal with all the cons of a big ('small block' based) V8. It certainly felt like plenty of power on the road but 250 to the tires just wasn't enough to tickle my pickle and brag about.

I also had issues in the summer, with a bed full of camping gear and a cab full of 2 humans or less, the truck would really struggle up mountain passes in terms of coolant temperature and apparently, fuel temperature.

There was a horrible clunking noise last time it was crawling in Moab. Made others uncomfortable. I didn't like it either.

So the shenanigans list was as follows:

Mo powa baby (happy at any improvement to tires, very happy with 300, hoping for more like 315)
Lower coolant temps in summer baby
No more fuel pumps crapping out on me on the trail, making Karens in late model 4Runners mad that they were delayed by 2 minutes while I rub an ice cube on my external pump
No more clunkity clunk on trail

[hiimmike]

How did you keep the ice cubes frozen in the Moab desert? ;)

[TyTheJeepGuy]

Many of the shenanigan list items have been tackled in my garage but with it still being Spring, I'm not sure if the goals were accomplished. There have been some promising results however, starting with the fuel pump.

I think I've been through about 4 external fuel pumps. Heat is what kills these mostly. They dissipate some heat via airflow over them but *most* is from the fuel that they push through. For one, that isn't good for making max power, but mostly the rejected fuel that ends up back in the tank has now been heated by a pass through the pump. Through the cycle of a tank of gas especially going through the mountains in summer the fuel would get hotter and hotter and the pumps would fail. Generally, this was associated with high coolant and manifold air temps so it was super fun having your pump die and your engine go super lean right when it was getting hot. Then you'd pull over and shut off your engine and watch it heat soak to the moon and blow out the radiator. Even more fun when you just lovingly rebuilt that poor engine and you're watching it get melted. Even more more fun when people are constantly questioning the reliability of your old rig and its blowing steam!

So, I dropped the tank about 5 times and installed a "pump on a stick" sending unit. This way the pump is constantly suspended in the fuel and I think it goes a long way for longevity. I bought an assembly made for a CJ5, the tanks look pretty similar. It turned out to do well. It can pump the tank to nearly dry which is great, has a "hydramat" on it so it handles fuel slosh a lot better than previous iterations.

Reason I had to drop the tank so many times was I was trying to bend it to just the right shape. There's a hump in the tank where the float for the sending unit needs to clear, it would get pinned up against it and not read full. Very hard to see and mostly guess work in a black poly tank. I eventually hit the right bend with very minute changes and a lot of swearing and crawling around and getting soaked in fuel. Not fun.

Anyway, my gas gauge reads decent now and haven't had a fuel delivery issue since! We shall see on Loveland pass this summer!

[TyTheJeepGuy]

How did you keep the ice cubes frozen in the Moab desert? ;)

Happily, all of the fuel pump overheating occurred on trips where I had my nice Yeti-clone cooler with a bag of ice in it :)

[TyTheJeepGuy]

Now, the lower coolant temps. This has been bothering me since the rebuild. I've got the 401 overbored 40 thousandths over, its getting real close to the water jackets. It was at about 9.8:1 compression, 1.3 over stock, and both of these things means harder to keep cool.

Here's the disappointing part. When I went to have this thing rebuilt, I was aware that the stock cooling system might not cut it anymore, and I bought an aluminum radiator *and* fan/shroud combination and fan controller from BJs offroad. For those of you who don't know, you have about 2 choices for Full Size Jeep specific shopping: BJs Offroad and Team Grand Wagoneer. BJO is almost always insanely overpriced. I spent a lot of money on that setup and really believed it was the right choice especially since all of the reviews were overwhelmingly positive.

The BJO setup did do quite well in a couple of scenarios where you usually expect a radiator or fan shroud situation to be the culprits: high ambient temps idling in traffic, and decently when going down (flat) highway. The FSJs don't do well holding 75, and I don't mind that. There are always compromises in a 70s truck.

However, it was just plain getting too hot in scenarios where it shouldn't have been. Going about 35mph up Loveland pass, I think ambient temps were only in the 70s if that. Engine would slowly outpace the coolant system, up and up to about 230f before the fuel pump went...

A1gemmel from this forum (big Yella Yota pizza truck snow-wheeler) helped me out big time. He put a ton of work into chopping up my hood and making it a big ol cowled hood. Even less visibility when offroading now but should help vent that engine bay. The engine still outpaced the cooling system though.

So, after trying tons of other things (different tune on the EFI, spark timing, even hooking up EGR to try and keep combustion temps down), I finally questioned whether the BJO rad and fan were really what they claimed to be.

I've been watching a ton of Roadkill shows and they almost always ran into the same problems with different builds. I noticed the Mopar cars had very similar radiators, the lower models had I think 22" wide radiators, while the "heavy duty" cooling for stuff like big blocks had 26-27". I noticed the BJO radiator is actually 22" wide, the stock was 26" wide core. In one of the shows they simply found the bigger 26" wide, tossed it on and had room for two electric fans, boom job done.

I started with the fan situation. I assumed that BJO's description was accurate: they claim that even though its only a 2 core, it is 2 1" cores instead of I'm assuming 1/2" stock so it actually cools better. I now think this is BS but will elaborate later. So, assuming the rad was kick-ass, it must have been an issue with getting air over it. The "shroud" that I bought separately is specifically made for the BJO rad, and is expensive as hell. The shroud isn't really a shroud, imagine more like a mid-plate for an engine mount. It sits quite flat maybe an 1/8" over the rad core. I truly think it only pulled air over the surface area of the fan. I think results would be similar or exactly the same if you just zip tied just the fan to the core. I set out to try and do better, but there's a problem.

The BJO radiator solution is THICCC and it was near impossible to find any fan that could draw more CFM that would fit, dual fan setups were too wide for the puny 22" wide core, and again with low space to the engine, coming up with a better flowing shroud seemed impossible. I bought a few fans before eventually giving up and sticking with their solution.

The issue bothered me enough, and I had recently set about for making more power. Which means asking even more out of the cooling system. I decided to reject the teachings of BJs Offroad and their reviewers with puny stock AMC engines ;) and set off on more research, this time into the radiator itself. I took some core measurements of the stock radiator I still had lying around propping my gate open from time to time and the BJO core. Crucial to cooling is total surface area and that's actually in 3 dimensions with radiators. The new radiator did in fact beat out the old one, but just slightly, and it seems that the cons of being railroaded into one fan setup that didn't have a very good shroud wasn't worth it. There is a *much* cheaper 3 row aluminum radiator that fits FSJ's (only listed under the AMC360 but, its the same truck) on RockAuto. I pulled the trigger on that. Also I found that there is a popular upgrade done by FSJ DIYers that involves using a turn of the century era Ford cooling fan assembly and it fits right onto stock AMC radiators (once you cut tabs off and find your own mounting solution): https://theamcforum.com/forum/contour-electric-fan-install_topic100667.html

I was super excited when the new radiator came in, and it fit! And has much more surface area for cooling. It also has more room to the engine so you can get fancy with cooling assemblies. If the Ford one doesn't work, I have a lot more aftermarket options, and a lot more junkyard cars should have them just sitting there waiting to be taken.

One thing with the RockAuto rad was that it did have a slightly more recessed mounting bracket, so the angle brackets used by the guys in that forum wouldn't suffice. I set about cutting up some corner brackets and drilling holes. I have a somewhat janky solution now but better for serviceability than the classic zip ties! The oil cooler for the transmission oil was back into the stock location so I trimmed up and remade my 6AN braided steel lines to go from transmission, to zip tied auxiliary oil cooler on front of core, to rad oil cooler, back to transmission.

This new setup is as yet un-stress tested but sure seems to move a great amount of air!

https://photos.app.goo.gl/DEBjhBjr3nwMp4gWA

[TyTheJeepGuy]

The eagle-eyed viewer may have noticed other happenings in the engine bay from the rad photos, that's the mo powa shenanigan. I'll be writing that up later.

[a1gemmel]

One of the coolest trucks out there! Here's a few pics of the cowl construction and the fuel cooler scoop. We were pretty amazed when we taped some string around the cowl/windshield and even at 10mph it was already inducting air!


https://i.imgur.com/PeO4s5Nh.jpeg

https://i.imgur.com/OOmFLm4h.jpeg

https://i.imgur.com/bJJj3u1h.jpeg

https://i.imgur.com/OVLawD7h.jpeg

[TyTheJeepGuy]

So for some context, that ridiculous fuel scoop was fabbed up (by A1gemmel) while I was installing my headers. I have a little fluid cooler (looks like an auxiliary oil cooler) that I had to tuck up under the truck and it got probably zero air flowing over it. Now it has air flowing over it for sure :) I think probably at the cost of 1mpg on the highway ;)

[TyTheJeepGuy]

https://imgur.com/ifDqJ5jhttps://imgur.com/ifDqJ5jSo for the clunking noise while offroading, turns out the transfer case I have (BorgWarner 1339) uses a drive chain for all modes: 2WD hi/low, 4WD hi/low. This chain got wore out over the years. I ordered a new one for the eye-watering cost of 340 buckaroonies from my favorite people, BJO. A1gemmel helpfully offers his shop for a more comfortable T case disassembly experience. I finally get everything apart and realize the new chain aint gonna work... turns out, my transfer case has an aftermarket kit that gives it 16% overdrive in all modes. This requires a different chain. Don't worry! BJO will partially refund you and make you pay a ton of shipping to exchange for the right chain.

When the new one finally came in I think I had that T case apart in about an hour in my garage, thanks to the practice run. Unfortunately also thanks to the practice run, it was well glued together by RTV and I had to use a jack to separate the halves. Cleaned it up, threw the new chain in on a workbench, heaved it back up into place and bolted back together with RTV instead of a gasket because the old gasket was disintegrated.

As with everything else in this thread, it is still unknown if this solves the issue, although there is a lot less violent clunking when shifting into reverse or downshifting now. :) Maybe if I stop tearing apart my running truck I'll be able to wheel it and see if the problem is resolved with a good ol loud pedal stomp in 4 low.


https://imgur.com/y0WMvxm.jpghttps://imgur.com/ifDqJ5j.jpghttps://imgur.com/7jUW3qP.jpghttps://imgur.com/MHuJ5Hh.jpg
https://imgur.com/wBpoFV3.jpg
https://imgur.com/a/IFjEGEx
https://imgur.com/a/IFjEGEx
https://imgur.com/a/IFjEGEx

[TyTheJeepGuy]

Check out this impetus for roaming around my property looking for things to sell to try and afford some nice Eddy heads for my poor suffocating 409! Blue is best run from July 2023. Red is from March 2024, after: wrapped short-tube headers, EFI and spark control tune, exhaust crossover pipe, no air filter!

I think it was clear that all the upgrades to exhaust doing nothing meant it wasn't my bottleneck. Which I probably knew already but figured that surely the headers would unlock a bit of power. Clearly the heads weren't flowing as well as the chaps on AMC forums would claim. We shall see... anyway, I did spring for some Edelbrock heads, and with some encouragement from a1gemmel I even attempted some very light porting and cleaning up on them.

I'd seen an episode of Hot Rod Garage with Tony Angelo. They bought these same heads (Edelbrock Performer RPM for AMC), slapped em right on without changing a damn thing, to an AMC 401 that was .03 overbored (mines .04) and with deeper dishes on their pistons. They did have about as big of a cam as you can put with the heads, I think .550 to my .448 (Edelbrock Performer instead of Performer RPM level cam, which is really a specific Comp Cam in disguise). Anyway, mine should be about 10.3:1 compression ratio, I think theirs was more like 9:1.

They made 450 peak hp at something like 6k RPM!! Yeah, I bought the heads basically immediately.

I finally got it back together last night and fired it up. Itching for a test drive but I've got a lot of garage cleanup to do, and the power steering bracket was broken when I went to take it off. I have a new one but I've got to get that rounded off high pressure line off to replace and I'm not really looking forward to that.

More details on the actual head install coming.

[xaza]

What an adventure you are having. If you are still looking for an electric fan, I have a 2 speed fan out of a Taurus 3.8L. I was going to use it for electric fan conversion on XJ but never got around to completing. You are welcome to it if you want. Picture of it is in build thread of XJ very top of page 6.

[TyTheJeepGuy]

Ooh darn I would definitely have taken you up on that. I was scouring junkyards before just getting a new one from Dorman. They say nothing pulls air like the OEM ones but so far these seem pretty great!

[FINOCJ]

The fun of old iron....many days I am ready to sell the 58....the engine is making a concerning noise. Been going with the let it blow a rod through the block mentality as that means I can start fresh again and stop chasing unending issues. Good luck....I originally joined the group when the 70 was still a bit uncertain, but once it got all worked out, it's been pure joy to drive and wheel all these last 8 years.....except maybe when I do something dumb (say smashing the rear quarter - twice! - or drive it into a big hole breaking stuff so jim can test out his both his winch and new welder/inverter)!

[hiimmike]

Do you know how many spare parts I'd have leftover if I tried to take something apart? hahahah

Before I lifted my Jeep, I didn't know what a tie rod was or what it was for. I learned a lot doing that work, good because now I know things if I break down on the trail. That or I just take Jim along who just tells me to pull relays until my brakes stop locking up. :lmao: I'm still dealing with that but I have a better fix, disabled all ABS systems/sensors with my Tazer.

[TyTheJeepGuy]

Short update: I'll still grab photos from the heads removal and replacement and do a better write-up of that. It was decently straightforward but a torn down V8 is always interesting to look at I think. Most of the interesting bits were actually to do with a mild porting job of the heads (at a1gemmels encouragement).

However the main update is, the new cooling system did very very well over the weekend. I was towing a snowmobile up mountain passes, holding about 3800rpm and heater off just to stress test it. On the way out the temps got up to I think 198 if I remember correctly. The ambient temps were low, snow was coming down near Eisenhower tunnel. The thermostat opens at about 185f, I turn on 1 fan with my fancy new relay setup and Holley Sniper output at 185f, then the second turns on at 190f. It rarely would overpower and climb past 190 in most situations where I was starting to hit over 200 easily with similar or lower ambient temps before.

Then on the way back, again holding about 55-60mph second gear going back up to the tunnel, no heater on to help, higher ambient temps this time, it climbed slowly to max of 214 and seemed to stay pretty stable there. This made me very happy.

[TyTheJeepGuy]

So, the mo powa shenanigan! The engine clearly needed to get more air. Since I had cooling issues anyway, some kind of power adder seemed like a bad idea. Even though we obviously live at elevation and play at even higher elevation I really like the simplicity of naturally aspirated engines. I came home from the dyno disappointed after upgrading exhaust (headers, crossover x pipe) and installing a fancy ignition timing system (Holley Hyperspark) and getting a tune. Same exact results on the dyno. I went looking for more info because when I was building my engine I remember the specs being similar to engines making something like 430 to 450 crank horsepower. My estimates based on the dyno put it to about 360 crank horsepower and that's being generous with the drivetrain losses. I did find plenty of internet evidence, for whatever that's worth, that the TH400 transmission is a power robbing slush box. Add to that some losses likely from the transfer case.

Anyway 360 crank I wasn't super excited about so I saw on an AMC forum that the Hot Rod Garage guys had an AMC401 that just kept asking for more and more fuel from the carb. This was surprising to me in 2 ways: for one I thought I'd seen all the MotorTrend shows I'd care about (mostly Roadkill based) and they almost always just stuck with Chevys, sometimes Mopars and rarely Fords, never AMCs. The second was that my engine was certainly not asking for more fuel, that meant they were getting more air than mine. I found the episode and loaded it up. There's a string of Hot Rod Garage episodes where they rip around that engine that I recommend watching, one where Randy Pobst (whom I've been lucky enough to meet on Pikes Peak!) tears it around a track. Basically they took a base 401 block, 30 overbored, put stock pistons in it and crucially, slapped Edelbrock heads on it. They claim that they did not touch the heads, just direct bolted on. The intake manifold is iron I think but some fancy aftermarket one, I'll chock that up to being pretty similar to mine (Edelbrock Performer). That thing revved up to 6k and made 450 horsepower. I'm pretty sure their compression ratio is maybe 9:1. So I ordered the heads that had been in my wish list for a while.

A1gemmel convinced me to do some mild porting or really just "clean up" on the ports and I'm glad he did. Not only do I think it probably unlocked some potential power here and there, but those things were DIRTY. Aluminum shavings coating all of the assembly grease. Valves were absolutely coated in aluminum dust. It probably would have been "ok" but who wants all that nastiness floating around their rebuilt engine? Not me.

Cleaned em up, reassembled, and set about tearing the truck down. I got it pulled apart pretty quickly, about a day's work if I remember correctly. Invited A1gemmel and my friend Zach over to help that evening. The help was nice especially for getting those crazy heavy iron heads out of there. Unfortunately, that was all that was left by the time they got there in terms of tear down, and I found out that I only ordered one head gasket and of course no stores are going to stock AMC V8 parts. Zach and A1gemmel and I discovered for me when we tried to at least install one head that I had also ordered the wrong head bolts. Edelbrock changed the head bolt patterns slightly. Luckily those arrived the same day the new head gasket did, and Summit was cool about refunding me for the wrong ones I sent back.

I had lost my help by the time the parts came back in, understandably (people have jobs and lives as it turns out). Luckily the new heads are nice and light, I think the truck literally sits higher in the front now. I was able to heave em carefully up into position and crank them down, 4 steps of torquing down all those head bolts. The rest zipped together relatively quickly and without issue; except I sliced my thumb open on the valley pan gasket that goes under the intake manifold. That made turning down all the little remaining bolts a literal pain!

Thanks to more help and my own efforts, I had really tightened down my wiring and vacuum lines in the engine bay. Some may say it still needs work but to me its great; I was able to put fuel and spark and accessories on relatively easily. Just a few minutes to get the Sniper back on there and ready to rock. I would find out literally last night (nearly a month and a trip to steamboat later) that through all this climbing over the engine bay I mashed a connection for the 12v power for the ECU. I'll elaborate on the intermittent issues that would cause later.

With everything back together it was time to fire it up. I of course had dropped the distributor back in 180* out, as is tradition. A couple massive backfires later and it was the right way, fired right up. Reset the static timing so the computer could take over and it was good to go. Of course at this point the hood is off and its raining but I couldn't help myself, I went for a glorious trip around the neighborhood. Aside from some stumbles here and there (12v power drop, as it turns out) the power increase was obvious to me. Big smiles per gallon!

I've got a busy May but I plan on a return to the dyno soon, and I'll post the results here. No matter how painful they may be its definitely the JMT now! (Jeep Muscle Truck). The Roadkill guys have a MMT (Mopar Muscle Truck) and CMT (Chevy Muscle Truck) so, I'm inspired.

https://imgur.com/tmLJcqP.jpg
https://imgur.com/ST3U4JW.jpg
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https://imgur.com/ozFQiCv.jpg
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[TyTheJeepGuy]

I forgot an important part that I think deserves its own standalone post on this thread. The Edelbrock instructions said I could reuse my stock rockers. I didn't know how that would work since those were held on by bolts, and the new heads used studs. Andrew didn't know how it would work either and spoke his mind, I unwisely ignored him while shrugging my shoulders. The sheet said its fine! Its fine! It wasn't fine. Turns out I need stock Ford small block rockers. Guess who happened to have them in stock for some unknown reason (he doesn't have any Ford V8s that I know of...)? Yup, Andrew. He brought them over and boom look at em! They're gorgeous. And they're roller tips so now I can rev to 7k no problem ;)

[a1gemmel]

The empire of dirt hides many secrets

[TyTheJeepGuy]

The empire of dirt hides many secrets


Wait is that thing I keep tripping on a Ford V8 block?

[TjMike]

That 401 is starting to look pretty! Cant wait to hear you rev that thing to 7k rpm :)

Seems like Andrew has quite the pile of parts laying around.

[TyTheJeepGuy]

That 401 is starting to look pretty! Cant wait to hear you rev that thing to 7k rpm :)

Seems like Andrew has quite the pile of parts laying around.

Thanks! I love the look of the aluminum heads. I was just joking about 7k rpm since I think you need to be in that range before the roller tips really make a difference. My cam is for idle to about 5500rpm and it feels like that's about where its at, maybe nosing over in power lower than 5500 about 5200 is my guess.

https://youtu.be/H1ArgVwGZgI

[a1gemmel]

Here's some good action shots I've taken of the ole honch'

https://i.imgur.com/NfWIWwKh.jpeg

https://i.imgur.com/14m2fCfh.jpeg

https://i.imgur.com/zhMSHtph.jpeg

Sorry Ty, couldn't resist :)

[TjMike]

I have questions about that last picture....

[TyTheJeepGuy]

When your friend drives a tractor you go from a dangerous side of highway fuel pump wire redo to an uncomfortable dirt pullout fuel pump wire redo.

[TyTheJeepGuy]

I've been busy with other things like visiting family for a week so unfortunately I haven't really felt the powa of the new heads too much. I'm chasing an issue where it will basically stall if you punch the throttle from a dig. I have a Holley Sniper expert looking over my datalogs and making a few changes here and there. Doesn't appear to be an issue with the head install itself at this point.

[TyTheJeepGuy]

I've got potentially good news, disappointing news, and good news for this build thread.

Potentially good news:
I think the V8 is making *big* power. As in, more power than the drivetrain was ever designed for... Worked with the Holley Sniper tuner and it finally started to be able to take throttle, and the whole front of the truck feels like its lifting in the air. Big smiles per gallon.

Disappointing news:

Short version:
Flex plate cracked (see potentially good news), transmission bellhousing cracked but not broken yet, Turbo 400 to Quadratrac (BW1339) T case adapter damaged, rear drive shaft slip yoke damaged.

Long version:
Was driving down I25 to drop off my wheel that I buggered up by forgetting to tighten that wheel's lugs after changing from winters at the airbnb for Moab in february. Just helped Andrew bring home a mill so what the hell, lets see what he can do with it. Up to this point, especially after changing the chain into my T Case, I had noticed slight vibrations that felt like drivetrain vibrations at certain speeds but I A) don't know what I'm doing with drivetrain stuff and B) checked all the bolts/nuts I had off for the T Case chain job and they all appeared nice and tight. I'm all smiles because the tune is *finally* appearing to take throttle and I'm feeling the new power on the highway. Not like it was boring before but it reminded me a lot more of my 485hp car now than it ever did before. I gave it a WOT then released, the engine goes to about 9 AFR reported by O2 sensor and causes a stall so basically engine braking. Suddenly a massive bang as my rear drive shaft slams into pavement at high speed, followed by tons of cyclical BAMs that I thought were from the engine at first. I pulled over immediately and turned the engine of ASAP still thinking it might be that. Hop out and see my rear drive shaft absolutely tunneled through the soft dirt on the side of the highway. Looks like the nuts retaining the slip yoke to the t case yoke had backed off, and the U joint might have been in need of replacement as well. This *likely* caused the T Case damage Andrew and I found yesterday. I removed the rear shaft from the rear diff on the side of the interstate and put it in AWD mode and limped it home on surface streets as soon as I got to the exit. The next exit was Andrew's so I actually just dropped the tire off anyway. Adrenaline crash was huge, that was probably the scariest moment of my life and I'm glad no one got hurt and I'm embarassed that I put others in danger on the interstate.

Since the adrenaline crash was so big I didn't have the heart to go get under the truck and inspect for damage that night, although I knew it would be a miracle if the only damage was too the drive shaft and maybe rear diff pinion seal (which was already starting to leak anyway). Next day I went out to a lot of ATF on the garage floor. I knew it was bad then but was holding out for a miracle. Got under it and didn't see any signs of damage, it looked like the ATF was leaking where the transmission bolted to the transfer case. At this point I thought the transfer case bolted right to the transmission but as it turns out, there is a cast aluminum adapter with a bearing in it for the transmission output shaft, the transmission bolts to this on one side, on the bottom is the "transmission" mount to crossmember, and then there are four threaded holes for the transfer case to bolt to. Then the whole big transfer case hangs out in space off of these 4 bolt points to cast aluminum... that to me is unbelievable. Just imagine the leverage with every bump on or off road that is ready to crack those things. Apparently this is not the only setup in offroad vehicles where this is a thing and even the Novak adapters still use cast aluminum but just with thicker "ears".

So, I know that there is need to inspect for damage and my theory is I at the very least need to try and replace the gasket between t case and what I think is the transmission but really the adapter plate. I very timidly and nervously drive it back out to Andrew's shop because I would like the help and the 4 post lift is a godsend for this kind of job. On the way I heard a noise I didn't like. Pulled over and it wasn't happening. Turns out it was only under "load" or in gear. I heard it again at Andrews shop and held on the brake with it in gear and asked him to listen. He thought it could be accessory belt but I had a feeling it was something to do with the torque converter, probably based on where it sounded like it was coming from. Andrew then suspected flex plate. We confirmed a crack in the flex plate once it was up on the lift. Yay! So that meant pulling the T case and Trans at minimum, and I wasn't driving home in my own rig. Its going to be a roller til I can get the right parts.

This leads me to the good news for this build thread! I've been wanting a stick shift romp-around vehicle (like maybe a CJ5) ever since learning to drive stick in order to get this 401 engine block to the machine shop borrowing Andrew's Ranger. When the T case chain started to go at Moab in February, I wasn't sure if that was what the problem was, so I thought if that doesn't solve it I'll start piecing together what I need for a manual swap. There are other reasons too, such as the gears being so insanely tall that even with good power it doesn't want to take off from a dig, or the power-sucking slushbox that is the TH400 (yeah you heard me fans of it, it robs power!) and I've been having to drop it to first with the tree shifter anyway despite replacing both the vac modulator and governor and it just won't go into first without being told to. So the good news for this build thread is I think that will be quite the interesting job putting together a manual swap. Andrew is suggesting a 5 speed manual which I don't think was ever in a FSJ so that will be interesting. I agree with his suggestion, more gears more betta.

Ok so, other findings once we had everything apart were nasty cracks starting to form on the bellhousing. Of course its a special case casting to mate up to the AMC V8 block even though the internals are the same as a GM TH400. We're going to attempt to fix that once I stop typing this and getting heading back to Andrew's shop. I'll post photos of all this happenings later.

The plan is to get a new T Case to trans adapter (ordered), new, stronger flexplate (ordered), and try to fix up the cracks in the bellhousing. This should get me back to doing fun things this summer instead of being bummed out, while I do research and start collecting parts for a manual swap. Hopefully along with the manual swap is a solid T Case with a better crawl ratio. I also plan on putting Andrew to work helping me put in the new 3.73 (3.54 current) diff gears and detroit locker that have been collecting dust for a year, but that has gone down the priority list significantly. :)

So, sorry if I miss some good runs with this crew this summer but I should be back in business in time to join for some or many.

[FINOCJ]

Wondering about the change from 3.54 to 3.73 gears - that is a very small change - like almost insignificant for the amount of work a gear swap is. I get wanting a bit more gearing, and the manual will definitely give you that even without a gear swap. If going with a 5 speed like an NV4500, you are going to get a wide range of crawl and OD potential. On the other end, running 35s and with a manual, it never hurts to have a bit more gearing, but I'd consider making the jump to something like 4.10 gears. Most ODs are about a .8 ratio, so 4.10 gears in OD run equivalent 3.31 gears in OD. So with an NV4500 and 4.10s, you'll get plenty of crawl in 1st, and on the street, using 2-5th, you'll get more off the line go as well as more highway friendly rpm cruise.

[TyTheJeepGuy]

Yeah the gears were bought when I was sticking with the automatic and was not getting very good highway range in 3rd gear. Didn't even realize I had 16% overdrive over stock in the T Case at the time, but I was worried about having too high of an RPM for highway miles. Hard to build the do it all truck with 3 gears in the transmission for sure, 5 would be nice. I think it does everything right now (well not with the trans and t case out of it) just not either end very well, crawling or highway driving. And that's fine with me anyway but didn't want to make it even worse with too high of gears.

Now that I have the 3.73s bought about a year ago and the detroit locker as well, I'll waste way too much money trying to sell and get taller ones. I'm going to be trying to piece together the NV4500 setup over maybe a year or more. The current setup, even though to me its a really dumb design, lasted something like 47 years and I gave it a good bit of abuse in the last couple. I'm going to see about making a custom steel brace to help the cast aluminum adapter replacement out, and the new flexplate I ordered looks to be far stronger in design so it can take the power upgrade.

[TyTheJeepGuy]

Photo dump from the Night of Sad Discoveries

[TyTheJeepGuy]

Oh I almost forgot:
https://imgur.com/3Q7YUb7.jpg

[TyTheJeepGuy]

So this build thread has grown a bit beyond the V8 up front but, likely related to the new power and probably just a mistake in not using the right mounting hardware for the drive shaft.

I have big updates from the last week or so so I'll split it into 2, out of chronological order for some reason.

Over lunch today my Charger will once again be the chariot for my rear driveshaft, I'll be driving it up to Boulder Driveline. I keep forgetting the guys name, I want to say Nick? Anyway the wizard there hooked me up with a new slip yoke but warned me he'd be surprised if I didn't need work on the drive shaft after the impacts like I had on the interstate. Told me to get the truck up in the air and observer the driveshaft rotation while in gear. I did so and it was clearly bent. Oddly, I had much less vibration on the "limp" home (just avoided highway speeds) than I was used to lately. I think driveline vibrations are a potential culprit for my transfer case adapter cracking.

If that comes back before the weekend I'll be trying to do a shakedown run probably up to Chinns or Fall River Reservoir this weekend. I won't be posting it as a calendar run for this group just because I'm not making a whole day out of wheeling, wheeling will be incidental and there's a lot of unknowns in terms of even getting up there :) but hopefully I'll be joining trail runs soon. I won't complain if some of you find me while I'm out there and say hi! I'll probably be fishing if all goes well. Also I'd love the truck to be in good enough shape to join up for the Full Size Jeep invasion at Ouray in July! I've never wheeled with another FSJ so that will be super cool. These are my people.

[TyTheJeepGuy]

Ok the slightly juicier update:

It took forever for my Ebay used TH400 to Quadratrac specific adapter/mount to ship. I finally got it in a week ago, Monday. That was the last piece of the puzzle. I decided while waiting, with the transmission and transfer case out, I'd finally make good on something I've wanted (at Andrew's suggestion a while ago) which is a higher stall torque converter. "Launching" higher in the power band sounded a lot better than knowing its making good power but pathetically lugging at every launch with too early of a stall.

Unfortunately with a new style of flex plate *and* a torque converter which technically does not list my application as supported I had created more variables than simply throwing everything back together but with new/used/unbroken parts. I'm really glad I dealt with this but it did end up taking more time in Andrew's shop. I was trying to get the truck out of his way in one day since he has about 8 projects to get to.

In hindsight, when considering the logistics of the job at hand and scheduling with friends' time for helping hands and my own commuting I would have just done this in my own garage. I've done (with help of course) engine removal, building, installation, suspension lift, complete fuel system, electrical, half of the transfer case in my own garage anyway. Andrew's lift was nice but I think I ended up doing as much crawling around as if I just was under it with a jack, and the jack may have made transmission install a bit easier. Plus if you discover your driveshaft is bent you don't have a 35 minute nailbiter of a drive home, let alone the limp out dumping ATF from a broken adapter. But I digress.

So I took a half day, wrangled up some friends to trickle in after work, and set to work on some of the things that still needed wrapping up despite my making several trips out to do things like the transmission governor, modulator, clean up and inspection, and helping(ish) weld the bellhousing. Thanks to Andrew for throwing like 3 different approaches to getting my cast aluminum bellhousing cracks welded up. We grinded along the cracks to give room for the weld to flow into. He did all the welds and on install day I had to grind back in several areas to clearance one of the bolts that go through the dowels. Speaking of the dowels, there appeared to be one left, who knows if we had the two normally between the engine block and the transmission last time the engine went in. Andrew spun some up on a lathe and my friend Chris cut and deburred them longways so they would fit in tight.

And speaking of things that go between the engine and transmission, there is a triple-purpose component that by some miracle survived the scrap pickup from my Dad's place when he passed away and my move to Westminster, and something like 5 years in my backyard rusting away. They are pretty cheap online surprisingly but I was glad to be able to rescue mine. I'll grab some photos of it and post here later. I think its called a converter cover plate, so it acts as a protective cover for the torque converter, a mild (2.5mm) shim/spacer for the engine to bellhousing, and apparently helps support the the starter motor. I was nervous about reinstalling it as never in my ownership of the truck have I had it there so that's just one more variable. It turned out great I think. For the first time I will have my converter and flex plate fully protected from the elements.

I got the flex plate ARP bolts loc-tited (I know they say not to but this was a re-install not initial with their special lube) and torqued to spec. The new flex plate looks so much stronger and is actually SFI rated so now I can finally do those 8 second Grand Dragoneer passes at the drag strip. Oh wait there isn't one ;)

As I said I was nervous about these new components that weren't technically supposed to work with each other. The pilot of the converter matches my last one but there's probably too much slop in the crank end thingy, I'm ignoring that... seems to be ok. Was definitely unsettling but at least the last one had the same diameter pilot both according to online specs and the digital calipers. I did at least mock ups and even some grinding on the ears of the (formerly) balanced torque converter to get it to fit within the flex plate. Just as others online had said, the "engine this side" sticker on the plate was wrong, and the ears of the converter had to be grinded down. Just AMC stuff. There's a little bit of visible throwout on the plate as the engine is running but I don't think its a concerning amount. I'm far from an expert though.

The cover plate set nicely on the new dowels and it was time to get the transmission in. We had it on a table that started buckling after dragging it under the truck on the lift, so we hefted it onto another and rolled it into place. We had some issues with the table not moving forward because of the yoke on the front axle but eventually we got the truck lifted down around it. Took a while to get dowel pin bolts slid through and started on threads. I wanted to make sure the trans bellhousing was solid on the dowels before locking down using the bolts, didn't need another crack in the bellhousing...

That all went well and the gentlemen helping me (Zach had joined just in time for transmission install) took a deserved break while I crawled around putting bellhousing bolts in and at least tightening them down a bit. The adapter had already been RTVd and bolted to the back of the transmission.

The moment of truth had arrived for the converter to flexplate mating so I set to work on that. I ended up shimming with two 3/8s washers to get the movement into good range. All 3 bolts went in, then back out because I forgot loctite. Then back out and back in because I didn't want a washer between bolt head and plate with the slim clearance to the plate/block. Meanwhile the boys were setting to work on the BJs offroad transmission mount that I don't think had ever been quite right. They had to shim it with a lot of washers sourced from Andrew's stash. That may have played a role in the eventual adapter destruction so big thanks to them for taking the time to do it right.

With the crossmember back up and the transmission fully mounted all that remained was the T case. Two of us hoisted it up onto the output shaft and got the splines aligned, then it mated up great. The gasket is already failing so IDK if it was a bad gasket, if I somehow didn't clean the faces up enough (that was a chore) or option 3. We got the 4 bolts in and torqued at least one of them to spec. At this point it was getting super late in the night and it was a wednesday night. It seemed so close and a shame to leave it after getting that dirty and that much done but I should have taken Andrew's advice and left it for the next day. Partly I wanted to not take up more time in his shop and partly I still did not know if the flex plate and converter were going to play nice.

I'm at least glad I stayed to find out the latter, we messed around unnecessarily with drive shafts for a while before setting the truck down on the lift so I could crawl in and do the not fun job of transmission refill. I have since gathered some cool helpers in my own garage that screw onto the bottles themselves and a top side creeper so I can save my knees and engine bay components. The days of crawling around the engine bay in my own garage at least are finally over. Anyway, we got enough to start the engine and I breathed a huge sigh of relief that everything seemed to clear. Eventually enough fluid went in to attempt putting it through the gears.

The truck somewhat wanted to move forward and backward but it was past midnight and we had to call it there.

I went back the next day, excited for my monster of a truck to roar again. It didn't really but that's ok lol baby steps. It took more fluid as is expected but we got enough in for a test drive. This was after noticing the driveshaft was bent. I'm glad I remembered to check that because if I hadn't I would have thought everything was fine since there's really no vibrations from it somehow.

The test drive was pretty fun. The converter is rated for 2400-2800 stall. Yes I know that's not great for offroading but I talked with Summit racing guys and said I wanted more fun launches and it was kind of the "do it all" truck but doesn't particularly offroad super well or race well at all, or go down the interstate for long stints very well, or tow large loads. Just kinda dips a toe in everything. Well this engine combination is having it stall somewhere around 3k rpm. I have since ensured it has enough transmission fluid with engine up to temp and going through the gears and engine running.

I've been taking it easy but did get into the throttle on a couple instances. Its a blast. I still have issues with the AFR delivery at hard throttle from a dig but I collected datalogs for the tuner to work with. When it does hook up it feels great. Massive smiles per gallon.

I have some concerns with this high of a TC stall, namely with transmission temperature. It was a hot day yesterday and it definitely got warm, it overpowered the cooling system for the first time since it was installed. Hard pulls into slow speeds it got up to 205 with the fans turning on at 185 and 190 respectively. I'll do another write-up on what happens with my goals of going up things like Loveland pass and Fall River Road (long slow hill climbs) without getting those aluminum heads too hot.

But for now, I'm just looking for a good tune and a straight drive shaft, and hopefully some Jeep fun this weekend!

Photos coming later but I didn't get many with how intense the reinstall was. Thanks to all who've supported the project so far.

[TyTheJeepGuy]

These are basically all the pictures I've got. I was over the moon at being able to finally put on the converter cover components that I didn't really know if they were for the truck but kept them around all these years just in case.

I'm going to pick up my drive shaft already (Driveline Services of Boulder are awesome!) so this thing should be on the road and ready for some summer fun shakedown run on Saturday. I'm still having those bad fuel tune problems and hopefully that gets resolved, but I'm out of my depth their so I'm relying on the remote tuner and getting datalogs made.

Just to be sure it wasn't a problem from my heads install I pulled all plugs and compression checked every cylinder last night. The new top side creeper I got on sale and the thin-wall specialty plug socket has made that job *much* easier.

[TyTheJeepGuy]

Ok so, back to AMC V8 shenanigans, although this time there was nothing seemingly wrong with the engine itself. The computer caused problems: who could have foreseen this?!

I think I mentioned before that I've been working with a tuner ever since putting the new heads on trying to get it to take full throttle. It just was not playing nice. He couldn't seem to get it tuned. At least every other aspect of driving it seemed fine. I finally got the redone rear driveshaft reinstalled and was excited to test drive the "With a Little Help From My Friends" Jeep. I had a great test drive to get a breakfast burrito, and it even took throttle from a dig!

Then, quite luckily but mostly unluckily, it started sputtering and dying as I pulled into my cul de sac. It finally fully died and wouldn't take any throttle at all on the driveway. I was able to restart it a few times but it horribly idled and was absolutely flooding the engine. I was able to start it and immediately give it throttle, throw it into gear and make it into the garage.

What followed was about 3 days over a weekend of thrashing on the fuel system. I changed basically every sensor imaginable or feasibly changeable. The MAP sensor and MAT sensors are built into the throttle body, not replaceable. Oh, and neither is the ECU. I'm running a Holley Sniper TBI.

I think the ECU was just dying a slow death. The tuner saw no signs of this but thought maybe an injector was getting stuck on. I tried a long list of things. Here's the list:

- new O2 sensor
- changed spark plugs
- changed IAC module
- checked for vacuum leaks
- tightened up upstream exhaust and crappily welded over the o2 sensor bung where there was a pinhole leak
- swapped rear injectors for front injectors
- checked injector harnesses and zip tied them down (common problem on Sniper but didn't appear to be my issue)
- changed the coil
- changed the coil wire (2 times)
- relocated coil

Eventually I decided to just eliminate the variable of it being the ignition system. I was running computer controlled ignition. I previously ran the Sniper with the HEI ignition I already had in it so I decided to throw back together. I got everything wired up, reconnected the negative on the battery and went to crank it. No RPM signal. Went to verify I had the right coil input setup correctly. Go to turn the key and there are now "NO DATA" displayed on every datapoint in the Sniper display.

So I guess the ECU finally played its last card and made it clear it was the problem. Before switching the ignition out I ordered another Sniper. I really wish they'd let you just buy the ECU. I was hoping I'd find the problem in the meantime and just send it back. This was not the case. I called Holley support on Monday and waited for them to get through the, no joke, 49 callers ahead of me. Guy with Kentucky accent tells me "yep, you fried it." I was out of warranty. They have send out options and you pay for the work and to get it back but I think it would basically add up near enough to a new unit that I just threw on the one from the box when it finally arrived.

Whaddya know, I press the gas and the thing takes off. I finally get to enjoy my sweet new cylinder heads! Big 409 power! But I will never financially recover from switching to EFI. I don't know if I would say I never would have if I didn't have to pass emissions because I do like the idea of self learning to keep the engine healthy in changing O2 conditions, but now I certainly wouldn't recommend the Holley Sniper. Maybe my new one will do better.

I did modify their harness a bit so that the ignition system is much less tied in, wiring-wise. They have separate 10 gauge ground and positive wires and they only share the switched 12v ignition courtesy of a distribution block. I also changed my "carb spacer" from an Amazon special phenolic to an at least more expensive aluminum part. I might have had an exhaust leak there but I don't think that would be enough to cause the catastrophic meltdown. Just want to eliminate all variables. I've chased enough electrical related problems now that I think I have really good quality connectors, wires and tools to make good connections, and I know my in-engine-bay wires inside and out at this point so I think i have a pretty solid setup now.

I made a custom spark plug wire for the first time ever and that's my new coil wire which is shorter and higher quality than the old one. Now I'm running MSD super conductors for every spark wire, with dialectric grease on all boots.

Oh shout out again to my buddy Zach for coming over the other night and helping me get a solid amount of work in, including as much of a distributor (re-)install you can do without a running engine and helping me pick out a good coil location.

My ultimate goal is to have fun this summer around town and try to make it to the full size Jeep invasion of Ouray this month!

[a1gemmel]

I think if I send Ty one more carb meme he's going to drive to my house and bludgeon me to death with the 600 afb sitting on his garage shelf

[Jim]

GREAT - but you certainly had to work for it.

From your write-up, these items catch my eye as good points to reinforce...

I think James / FinoCJ (Mr. Carburetor) can comment on changing 02 conditions...

I finally get to enjoy my sweet new cylinder heads! Big 409 power!

I do like the idea of self learning to keep the engine healthy in changing O2 conditions

I've chased enough electrical related problems now that I think I have really good quality connectors, wires and tools to make good connections, and I know my in-engine-bay wires inside and out at this point so I think i have a pretty solid setup now.

[TyTheJeepGuy]

I think if I send Ty one more carb meme he's going to drive to my house and bludgeon me to death with the 600 afb sitting on his garage shelf

There's nothing more frustrating than when the troll is right, is there?

[TyTheJeepGuy]

What does James have to say, that they're negligible? I'm guessing that's probably true. I know Andrew doesn't rejet for different elevations but I don't know if a displacement difference plays a role.

My former employer's Dad apparently used to bring a whole separate carb and pull over at some point along I70 and throw it on for the rest of the weekend, I'm assuming while laughing at his son and his friends having to rejet theirs.

[TyTheJeepGuy]

The new Sniper unit worked great. I also *finally* got a chance to get back to Fall River Road in July weather on Saturday I think around 4 in the afternoon. I admit I didn't check the ambient air, it didn't seem to matter too much when it came to overheating on that road with the long slow ascent.

Previously, with the iron heads and BJs Offroad radiator and fan combo, the truck would get close to 240 degrees and start spewing coolant, especially once I pulled off the road that the top in that little St Mary's neighborhood. The technical service manual says that's normal and the "good" (green) range on the thermo guage goes up to 247. Right now I have my coolant sensor feeding my Sniper ECU so I am not sure what the gauge reads but I also now have those aluminum heads that I'd like to keep cooler than the iron heads if possible. I was not ecstatic but decently happy with the improvement from my new half-custom rad and fan setup (Ford Contour fan assembly modded to fit AMC 3 core aluminum radiator). Especially cool was the fact that 226 happened right near the end and by the time I was pulling into the neighborhood it had already cooled to 220. Letting it idle the water through brought it back to 195 in short order.

Also, the in tank fuel pump didn't die on me! The external ones would often die on the trail or on long slow hill climbs, sending the engine lean and eventually dead so that it would heat soak on the side of the road while the coolant erupted in a dazzling display for all to see. Or in one case an angry late-model 4Runner owner was very unhappy to be blocked on the trail for a full 2 minutes while I iced the pump. I will never forgive myself for absolutely maliciously ruining her entire day, with intent.

I'm a bit disappointed with the torque converter, its definitely awesome punching the gas and launching at 3k rpm but this is a Jeep truck and definitely not a drag racer. The advertised stall range was 2400-2800 and I'd be a lot happier in that range I think. Its basically slipping the whole way up on highway in third (final) gear and the engine rpms are pretty high in second gear. When it slips I imagine its dumping heat into my transfer case cooler which looks like it might take up something like 40+% of my rad surface area and it also goes through the integrated oil cooler in the bottom of the rad. When it isn't slipping I'm holding over 3k rpm under load with a pretty big V8 so that's not exactly easy to keep cool. Considering all this I'm pretty happy with the 226 as a high number in July on a hard test. If I can make it over Loveland pass with a full load of camping gear only getting up to 226 or keeping it under 230 at least without the fuel pump dying or losing coolant, I'll be quite content.

For my test I first went all the way up to St Marys, then backtracked a bit and helped my friend park his car and transfer some camping gear to my truck. We went up to where the fork for Fall River Res or Chinns splits and had an excellent campsite considering the national holiday weekend right there at the fork. Once camp was set up we went up to the lower Chinn's reservoir which had a couple of minor rock obstacles and a deeper than I'd like on a shakedown-run puddle to wade through. The truck performed admirably and we got to soak in the lake view and drop some fishing lines in before heading back down to camp.

There's a leak between the transmission and transfer case that I'd like to resolve, a bit of Full Size Jeep forum research and it looks like in some applications the paper gasket itself doesn't work. I'll just order another and add some special Rite Stuff RTV sauce where I see fit this time and throw it back together.

My brother is in town this week, he was present for the first dyno test and he might be present for the 3rd, this time I am thinking its going to make 340 (SAE adjusted) to the tires. At least, that's based on me thinking the engine build should give about 409 horsepower, one per cube. I'm counting about 20% for slush box TH400 and transfer case chain loss. Won't be disappointed if its less though, there's a lot at play that far removed from the crank.

[FINOCJ]

What does James have to say, that they're negligible? I'm guessing that's probably true. I know Andrew doesn't rejet for different elevations but I don't know if a displacement difference plays a role.


I am a big fan of rejetting....but it's not always practical to do at a trailhead. Remember that atmospheric concentration of oxygen changes a lot more between sea level and 5000' than between 5000 to 10,000'. It's not a linear decline...so it's important for those that travel to Colo from the flatlands to reject, but if you live at 5000' in Denver, it's less of an issue even when you go uo to 13,000'. I still run what I ran i. Denver in terms of jetting, which is a bit lean for 5000', but I rarely go below that. I am jetted for about 7500', which is more where the jeep runs in the mountains most of the time. It does mean in Moab at 4000', I have to be aware of running too lean, but with relatively low compression it not likely to have predetonation issues, but it could cause it to run a bit on the warm side. What is practical at the trailhead is to make adjustments to the initial timing ....going up in elevation the engine will run better with more advance. And if I go to Moab in hot weather, dialing back the advance would help with overheating if it ever was an issue. And if needed, I do carry a couple different jet sizes in my parts bag (along with other carb stuff) but never needed them or wanted them after getting it 'right'. At the same time, the 58 with SBC is moving toward TBI with learning capabilities to manage Oxygen fuel mixture....but keeping the mechanical distributor advance for now.

[TyTheJeepGuy]

Was driving around with my brother in the truck when the battery voltage went down to 12.5 steady, we pulled off the highway and checked it out. All grounds and wires looked good, belt was turning the alternator fine. Got it home and pulled the alt the next day and the cap on the unused internal regulator connections was absolutely fried. Something had fried. Decided I'm done paying for these alternators so I bought a GM 3 wire. That took a while to figure out, and boy is it hard to find a diode in a store these days. I miss radio shack.

Either my brother or I stripped the bolt from the alt bracket in the new aluminum heads, so I had to drill it out and helicoil it. While the truck was out of action I decided to install a remote transmission fluid cooler with its own fan harness so we had a full saturday of truck thrashing. The reason for this change was the old aux trans cooler was taking up something like 50% of the front of the radiator, as well as running fluid through the integrated oil cooler in the rad, and with the converter slip I couldn't help but imagine that was dumping heat onto my already barely big enough radiator, especially on slow hill climbs. It does however add a point of failure and I don't have a monitor for transmission temps so I'll probably be adding that soon. The relay for its fan is triggered by accessory power. I used nylon-braided 6an lines for that.

On Wednesday I leave for FSJ Invasion in Ouray! Stress tested the truck yesterday going up to Yankee Hill and it did well in terms of coolant temps on the climbs, and got me there and back without issue. Hopefully the Ouray trip goes without a hitch.

[Jim]

got me there and back without issue.

:thumb:

[TyTheJeepGuy]

So the truck did Ouray FSJ invasion in July, did some solid offroading and interstate miles on that trip. Even held 75mph in heat of the afternoon and no cooling issues. That's with a torque converter that doesn't want to lock up until 3100rpm so that's what I held for hours on end... wasn't happy with that but amazed that it stayed cool.

There'd been a consistent leak since putting the new t case adapter back on and I had a few things I wanted to do before going on the long overlanding trip Andrew had planned for breaking... in his new trailer. So I dropped the Quadratrac alone in the garage, I only had a mark on my belly from it for weeks its fine. Slapped RTV on either side of a new paper gasket and pushed them back together. Solved the leak! Unfortunately while stunting on some weak Toyotas on a hill climb, I ate a big ol piece of humble pie. The Quadratrac transfer case just isn't the beast its said to be online. I stretched out that fancy BJs offroad 340 dollar chain and now the t case slips gear teeth under heavy load.

When I emailed them to try and find out next steps instead of throwing another 340 dollar chain every month or babying my big bad truck they claimed that no one, had EVER, stretched one of their chains. I call BS but clearly it just wasn't going to work for my application.

The venerable TH400 was popping leaks left and right that I couldn't seem to solve and I had to manual shift it to take off in first gear, and the high stall converter was fun for loud faster take-offs but obviously had way too many drawbacks. You have almost no options for what to adapt to the back of it without changing the output shaft and I'm done with the Quadratrac. So, it looked like the next steps were the "maybe one day" NV4500 and NP205. I've collected those and been in the process of the swap. I'll get another write-up on here with more images for my next post.

https://photos.app.goo.gl/6YWfeJKgjdPXW51h7

You can actually here it clickety clack in that video, enjoy :)

[TyTheJeepGuy]

I want to get the right part numbers and everything in the manual-swap build post, and I haven't even completed the job, but in the meantime here's some photos of the "new" transmission and transfer case. The transfer case came attached with an SM456 and Andrew came out to help me collect them, fittingly the J10 was the mule for going to get its new guts. The NP205 and SM456 were picked up from Masonville by Horsetooth reservoir which was a cool nostalgia thing for me since that's where my Dad used to live when I'd visit him in grade school.

[Jim]

You can actually here it clickety clack in that video, enjoy

oof.

And now there are interesting parts at hand...

[Mountaineer01]

You're an expert at this point of removing transfer cases and transmissions.. You want to fix my rear main seal? :D