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KnuckleHead
June 5th, 2011, 09:58 PM
Was wondering if anyone can tell me what causes dog tracking? I believe thats what it is. You know, when your driving down the road and your truck looks like its driving side ways....... just seems to be off.

I'm not sure if I have this problem or if its the width of my tires... 15.50. I seem to be all over the road and it's worse if there is wind. Also when coming to a stop I look like a drunk that can't keep her straight. Anyone have any ideas?

Thanks

Rob
June 5th, 2011, 10:08 PM
Are you saying it tends to jump to one side or the other when you're driving?

I had that problem with the FJ40 when it got new springs and a lift. I ended up replacing all the steering rods and ends and rebuilding the drag link end and the bellcrank. It still wanders a bit but it doesn't jump around anymore.

4finger
June 5th, 2011, 10:11 PM
if i dont have my iroks full of air i wander all over the place. im actually scared to drive on busy roads with it. as far as braking goes i think all solid axle vehicles with a lift drift when the brakes are stomped on. i can almost change lanes if i stomp on my brakes hard enough.

Rob
June 5th, 2011, 10:22 PM
if i dont have my iroks full of air i wander all over the place

Interesting. My FJ40 handles better when the BFGs are at about 25 psi. If I go up to 30 or 32, it starts to wander.

foxtrot
June 5th, 2011, 10:32 PM
its that same way on my rig, I drove back from penrose with 15 lbs of air in my tires, and my alignment was a little off ( pointing outwards) and when I hit my brakes, cars seem to move further away from me lol

Haku
June 5th, 2011, 10:32 PM
Not sure on the name either, but I've seen plenty of rigs (including mine evidently) where the rear axle is quite straight on the to frame i.e. the front axle isn't parallel to the front one. Lots of reasons for it that I can think of, but not sure on yours. It could have shifted on the leaf springs a bit, or the leafs themselves could be sitting weird. Lots of different things. Doing a comparison between the sides of the rig is the only real way to tell that I can think of. Make sure the axle housing isn't bent/warped too.

The steering under breaking issue sounds like a caster issue. Essentially when your rigs nose dives as you break, its rotating the axle enough to destabilize the rig. Its either that, or you are getting some bump steer. Bump steer is when the steering drag link pushes on the steering arms when the suspension moves.

Its hard to make guesses on stuff though, and its hard to tell just by looking at stuff what the issue is. Its a process of elimination kind of thing, where you make a change and see if it fixes it.

Patrolman
June 5th, 2011, 10:33 PM
It can really be a number of things. Bent rear axle shaft or housing, bent rear spring, axle shifted on the rear springs, bent shackle, etc. Could also be front end, but not as likely I think.

4finger
June 5th, 2011, 10:51 PM
If I go up to 30 or 32, it starts to wander.
according to my "friends", its hilarious to follow me when we are heading back from the trail( since i dont refill my tires), and watch all the cars make a WIDE berth around me. one of the main things is the ruts in the road. i was in the process of looking over my shoulder to change lanes and by the time i looked back i was already in the other lane. if my tires are full (30 lbs or so) i can cruise at speed and even let go of the wheel if i want. i drove from here to moab (the back way over john brown canyon) without any steering/wandering issues. tires were full.

Hypoid
June 5th, 2011, 11:30 PM
It can really be a number of things. Bent rear axle shaft or housing, bent rear spring, axle shifted on the rear springs, bent shackle, etc. Could also be front end, but not as likely I think.Bent or twisted frame...

When I had my Chreokee on the alignment rack last weekend, I watched the tech set up his equipment. I asked him if it would tell that my axle was not square to the frame (accident damage). He replied that they align the front tires to the back tires, and that a vehicle could drive straight down the road and still dog track.

Brody
June 6th, 2011, 07:01 AM
Generally speaking, the axles aren't aligned, whether from the frame being bent or anything else that people have mentioned.

Lay down two pieces of long anything: tubing, 2x4s..whatever you have laying around, stick these on either side of your rig the same distance apart. Get your wheels straight. Measure from board/tube to tires all the way around. You can also double check junk by attaching a nut to a piece of string x 4 and looping it over you axles so that the string hangs free (loop it over the inside of the axle front and back) measure from string to string on each side. This will tell you if your axles are parallel to one another.

Take a look at the spring perches front and rear to see if there is any 'shift' marks on the springs. Could be that the center pin got toasted and the axle has shifted on the mount.

15.50 tires are going to grab pretty much anything in the road and you will 'track' a bit. It is going to be even more important to keep the same pressure in the tires, especially in the front , due to the width. Do the chalk or light colored marker test on the tires to see if you are running the right pressure for the street. The diving to one side or another is most probably due to a worn shock or bad/sticky caliper. If the caliper grabs, it will pull to that side. If the caliper is not grabbing because it is shot, it will pull to the opposite side. Also check your spring mounts on the front for the same reason as the back. If the center pin is toast, then the springs will have shifted. If you have lost the center pin in one or the other of your front springs, then the rig is going to shift when you stop.

KnuckleHead
June 6th, 2011, 08:34 PM
Thanks for all the feed back..... I will start looking/testing this week when I have time after work......