Rear Wheels Binding

[KristinIsGreat]

Have a 2001 Silvy 2WD 5.3L, no mods to rear differential.

Occasionally when I'm running it pretty hard for awhile, I'll slow down and the rear wheels will bind a bit when I take a slow turn. I'll simply drive it around the block at a slower speed and it corrects itself. What worries me, is lately it's been binding from a cold start (however, not binding before I park it the night before).

Have changed fluids in rear differential - hasn't changed a thing. Any ideas? Possibly a toasted limited slip gear?

[kenny-1907]

What do you mean by bind ? Do you know if you have a posi in there or not for sure ? if you do , when you changed the fluid did you add some limited slip additive ? Does it make any noise when this binding occours ? It could be something as simple as the locking diff being locked tight from you beating on it, i had a governor style posi in my old 88 full size jimmy in th efront that would do that, or it could be ready to grenade on you. Either way i would probably take it in and have a pro look at it, most places will take a look at it for you usually at no charge if there is a possibility of them getting the business of repairing it.

[KristinIsGreat]

Originally Posted by kenny-1907

What do you mean by bind ? Do you know if you have a posi in there or not for sure ? if you do , when you changed the fluid did you add some limited slip additive ? Does it make any noise when this binding occours ? It could be something as simple as the locking diff being locked tight from you beating on it, i had a governor style posi in my old 88 full size jimmy in th efront that would do that, or it could be ready to grenade on you. Either way i would probably take it in and have a pro look at it, most places will take a look at it for you usually at no charge if there is a possibility of them getting the business of repairing it.

great info, thanks for your help!

[KristinIsGreat]

by binding, I mean that it seems like something's locking up in the gearing. The truck is still rolling, but it's making a noise somewhat similar to the noise wet brakes make when you're creeping to a stop - not a squeak, but a gutteral sound. The truck lurches back and forth a little bit until it's going straight again. It's only on slow turns, not only when I'm beating on it beforehand, but lately from cold starts as well...it's inconsistent at best.

I definitely know there is a posi in there, didn't add limited slip additive when I changed the fluid.

I think you're on the right track taking it in for a checkup - again, thanks for your help...

[jumpingjack66]

My locker does this at times, i am reluctant to call it "normal" but i think if your not used to a locker then it can seem like its binding or having problems. Mine always scrubs a tire when turning, that just tells me it is still working...jj

[Rhymingmechanic]

2001 2WD with posi and traction control--I have never noticed any noises like you describe, on turns or even parking lot figure-eights (I did that to check for rearend noises after changing fluid). The only sound the rear makes is a quick clunk or knock on engagement going straight, but I think that has more to do with traction control than the locker.

If I understand these axles right, they lock with a spinning governor, not by clutch and spring pressure like the traditional posi. I did a lot of research before changing fluid, and apparently the limited slip additive is not needed, but probably won't hurt anything.

What fluid did you use? Before taking it to a shop, it might be worthwhile to add limited-slip additive and see what happens. Try 1/2 bottle and do some figure eights. If the noise is still there, add the rest. Otherwise, it seems like something mechanical. Good Luck.

[RahX]

i looked up on alldata which diff came in the truck and both are clutch type diffs. i would suggest some friction modifier for your fluid to decrease the chatter coming from the diff. you can go to teh dealer and get a bottle of it and just add it to whats already in there or you can go to a parts store and see if they have something equivalent.

[Rhymingmechanic]

KristinIsGreat--

If adding friction modifier doesn't help, it might be worthwhile to pull the cover and look inside. I just found this on another Silverado board:

"This is out of my 99 silverado with 255,000 miles on it. It was still working but staying locked around corners."

He included a picture that showed cracks in the differential.

[twomorestrokes]

My '02 has an Eaton locker in it that uses steel plates and a governor style locker. Synthetic lube but no friction modifier is recommended.

[Shortbus]

GM released a bulletin about the additive (gGM part# 1052358)about 3 years ago we now only add it to f-body rear ends. I don't remember the details but it stated that if you buy the GM rear axle lube then you don't need the additive. The additive was foaming in the diff and causing venting problems. I would assume by now most over the counter aftermarket oils have followed suit and upgraded their 80/90. Not positive though.

[twomorestrokes]

Originally Posted by Shortbus@AF

GM released a bulletin about the additive (gGM part# 1052358)about 3 years ago we now only add it to f-body rear ends. I don't remember the details but it stated that if you buy the GM rear axle lube then you don't need the additive. The additive was foaming in the diff and causing venting problems. I would assume by now most over the counter aftermarket oils have followed suit and upgraded their 80/90. Not positive though.

The additive also produces negative results when used in the Eaton. My friends at the GMC dealer call it snake oil and do not use it.

[dmilacek]

Originally Posted by twomorestrokes

The additive also produces negative results when used in the Eaton. My friends at the GMC dealer call it snake oil and do not use it.

So what do you suggest? I changed my fluid with the GM synthetic and it did not help the problem. It is intermittent, but is happening with more frequency. If I break the tires loose, it locks up, and then will not unlock easily. If I corner, it slips the inside rear tire and clunks. Only have 50,000 miles, at present. Need to do something. If I take it to the dealer, I may as well throw money out the window.

[kenny-1907]

dmilacek, if it is locking up and clunking around corners i would get it looked at real soon cause that is the same thing mine was doing and this was the result........