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Brad
May 3rd, 2011, 12:05 PM
Hey everyone! I am posting this on multiple sites to see if anyone has any knowledge of this problem.
This is keeping me from wheeling so I need to get it figured out.


First some specifics:
1995 Disco
Automatic transmission
Added 245 75 16 BFG MT KM2 tires
Welded on Sliders
Complete Transmission service done (including filter) at 180,000 miles currently vehicle is at 185,000 miles, added BG auto trans additive to
transmission and factory recommended trans fluid. All 3 differentials have
85w 145 synthetic valvoline as recommended over on LRF.
Drove to moab at the end of March towing my pop up camper. No problems going to moab, did alot of 4 wheeling while there. No problems. Drove back and had a tough time getting up Vail pass from the west side and up eisenhower tunnel from the west side. Drove fine for the next day after getting home then developed a really harsh shift.
Let me explain what this is like.
Take off from a stop-> vehicle shifts normal up to 2nd, revs up to almost 3500 before shifting into 3rd. Usually I let off the gas and it pauses then
BAM!!! slams into overdrive. Hit the gas and it downshifts back to 3rd just fine then have to let off the gas and BAM!!! slams into overdrive again. This happens over and over again. Will also happen if I slow down and it shifts down to 2nd then coast BAM!!! slams into 3rd and then again into overdrive.
Anyone else had this problem?
scout man
May 3rd, 2011, 03:08 PM
What kind of tranny do those things have? Sounds like if its something with bands, then your bands are slipping. This is just a guess, as I havnt seen the tranny, but that is what pops into my head first. From there I would look at too little/too much fluid, or something clogging a line somewhere.
Brad
May 3rd, 2011, 03:09 PM
It is a ZF 4HP22
Aaron
May 3rd, 2011, 03:14 PM
Call the queen!
transplant87
May 3rd, 2011, 04:01 PM
i agree with steve, i would look at ajusting the band a little. and did u go straight to full syn or did u use the blend.
Brad
May 4th, 2011, 09:10 AM
So far it looks like I have 8 different answers between all the posts I have up and my research on the subject.

I am more confused now than I was to begin with.
scout man
May 4th, 2011, 09:14 AM
Try getting the rebuild manual on it. The one for my tranny has a great troubleshooting section to help out with stuff like this.
Brad
May 4th, 2011, 09:22 AM
You know.. I never thought of that. I have the rave manual (full pdf version of the shop manuals the dealerships had). Perusing now.
edog
May 4th, 2011, 10:34 AM
I am by no means suggesting this will work, just adding it for some info it might possibly provide. I had a Saturn SL1 that developed some seriously hard shifting and would slam into gears, especially reverse. This was a common problem for the Saturns and even has a name (the reverse slam!), the solution was weird but it really did work. I changed to fresh tranny fluid and added a full bottle of Lucas anti slip. Then, I let it idle for 30 min- 1hour in reverse against a wall. Something about circulating the anti-slip fluid through the tranny resolved the problem. I don't know anything really about auto tranny's but this worked for me. Like I said, this is apples to oranges, on a light duty car, but maybe something in there would help you out.
Chris
May 4th, 2011, 10:45 AM
Just adding to confusion for you Brad but on the FJ62 we would get it up to 50mph and throw it in to reverse for a second. Yes, I'm serious and did it on mine to free up some sticky valve in the tranny. It works!

I take no responsibility for what it could do to your truck though! :eek:
Aaron
May 4th, 2011, 10:49 AM
You know.. I never thought of that. I have the rave manual (full pdf version of the shop manuals the dealerships had). Perusing now.

I finally get to use this smilie... :rtfm:
Aaron
May 4th, 2011, 10:49 AM
Just adding to confusion for you Brad but on the FJ62 we would get it up to 50mph and throw it in to reverse for a second. Yes, I'm serious and did it on mine to free up some sticky valve in the tranny. It works!

I take no responsibility for what it could do to your truck though! :eek:

:what:
Chris
May 4th, 2011, 11:38 AM
That was my thought too Aaron! It's called Rodney's Party Trick after the Australian expert on the Toyota A440F transmission. It really does work and there are plenty of testimonials to support it.
Brad
May 4th, 2011, 12:14 PM
Just adding to confusion for you Brad but on the FJ62 we would get it up to 50mph and throw it in to reverse for a second. Yes, I'm serious and did it on mine to free up some sticky valve in the tranny. It works!

This sounds like a advertisement for a sheister transmission shop. :D
Metalhed
May 4th, 2011, 01:26 PM
How about Vacuum leak. Not even sure if the truck uses any vacuum for the trans but ?????
Funrover
May 5th, 2011, 10:22 AM
What transmission fluid did you use to replace in your trans service? In the rovers that can make a big difference. The mobil 1 works great in mine, however the Dex III made it shift hard just as you are describing.
Brad
May 5th, 2011, 11:18 AM
I think I used Dex III. I may also have a clog in my trans cooler. The fluid that came out was terrible on my first flush.
Chris
May 5th, 2011, 02:27 PM
I burned out my tranny due to the cooler being clogged, it's not a pretty site when it goes. Glad you're on top of it!
Brad
May 5th, 2011, 03:34 PM
Result!! I went and checked the kickdown cable to the transmission and the adjusting nut had vibrated completely loose. Transmission had no idea where the throttle was.
Shifts smooth as butter.
Chris
May 5th, 2011, 03:36 PM
Nice easy solution, congrats!
Stephen
May 5th, 2011, 03:49 PM
Result!! I went and checked the kickdown cable to the transmission and the adjusting nut had vibrated completely loose. Transmission had no idea where the throttle was.
Shifts smooth as butter.

Good job!




I see Randy has taught you well, Grasshopper! :D
Brad
May 5th, 2011, 03:50 PM
I see Randy has taught you well, Grasshopper!

OH NO YOU DINT!!! I AM GONNA RIP YO HAIR OUT B***H!! :D
Stephen
May 5th, 2011, 03:52 PM
OH NO YOU DINT!!! I AM GONNA RIP YO HAIR OUT B***H!! :D

:D


I knew you'd like that one! I have pics on my old phone of him sleeping in PDIs! lol
Brad
May 5th, 2011, 04:01 PM
Post them up! :thumb:
scout man
May 5th, 2011, 08:23 PM
hmmm, kickdown lever... i removed mine in moab. It kept getting in the way. one of these days I will reinstall it though!
Funrover
May 6th, 2011, 09:07 AM
Good to hear.
Fordguy77
May 7th, 2011, 03:33 PM
hmmm, kickdown lever... i removed mine in moab. It kept getting in the way. one of these days I will reinstall it though!

Same reason i went from a bar type to a cable type on the 77.
Brody
May 8th, 2011, 07:55 AM
Result!! I went and checked the kickdown cable to the transmission and the adjusting nut had vibrated completely loose. Transmission had no idea where the throttle was.
Shifts smooth as butter.

Nice to find a simple fix that doesn't break the bank! Happy to hear!
scout man
May 9th, 2011, 06:31 PM
Same reason i went from a bar type to a cable type on the 77.

yea, the first tranny i had had a nice clip to keep the kickdown lever in place, the other 2 have not. Unfortunately I lost that clip along the lines somewhere and havnt found another one. Had it cable-tied on for a while, but that finally broke. Never really liked how it shifted on its own anyways, and since its a 3 speed, I just shift it manually.