crankbender

I on my 94 manual have noticed a lurch / bump / binding feeling when turning sharp corners. The feeling is very much like the one you get when the truck is in 4WD and you try to turn sharp on pavement....exept the truck is not in 4WD and the feeling seems to be comming from the rear end.

I had the front U joints replaced today, they were worn fairly bad and I was hoping that new ones would cure the problem but they did not.
The rear U joints are good and there is not to much play in the rear end.

Any guesses as to what is causing the lurch / binding? It only does it when you turn quite sharp and is worse when first taking off from a dead stop. I can feel it about 3 times then it seems to go way.

One other thing, I noticed a bit of up and down/side to side play in the shaft comming out of the transfer case and going to the rear end. I pointed it out to the mechanic when we did the U joints but he did not think it was that bad but pointed out that seal leaks oil. Could the Transfer case be causing the problem?

kawi600

Id check that the truck isnt in 4wd. Make sure the cad and vacuum lines are working like they should.
Then Id look at the spider gears in the rear and see whats with those. Universals are also suspect, both on the axle and in the driveline.

crankbender

I had checked that the truck was not in 4x4 by puting it 4 high and turning on pavement. I can tell for sure that it is going in and out of 4WD.

I took the truck out this morning and did a lot of testing in an empty parking lot. The problem only seems to happen when starting off slowly from a dead stop with the wheels turned. I am starting to think it is the rear end binding up as one wheel is turning faster than the other. Could the limited slip be causing this? Is it ajustable? I know for sure that the Diana 80 in my 02 would not act like this.

1-2-3

Have you ever changed the fluid in the rear dif?

crankbender

Nope, never changed the rear diff oil, I just bought the truck last week.

I took it out just now, after installing a BHAF, seems I can only make it bind when turning left. If I start moving while turning left, it will clunk a few times. If I let off (so the gears mesh the other way on decelleration) then go again I can make it clunk again.

Pretty sure it is the rear end.

How much do rebuilds cost?

jughead

sounds like a posi-unit that needs more additive to me

Crimedog

That's just your limited slip. If it bothers you pick up some friction modifier and add a little bit at a time. After adding a bit go do some figure eights and see if you like it better. The clunking is just a little bit of slop in your ring and pinion, unless it is REALLY excessive there is no reason to worry. I'd change the gear oil since you don't know when it's been done, then pick up a tube of limited slip friction modifier and add the recommended ammount. Too little and it will shudder, too much and it can wear the clutches out over time. Good luck!

crankbender

Thanks guys, I will change out the oil and pick up some of that friction modifier. Hopefully that will help it out.