Rear wheel drags in turn

[wmhall]

New on the site and all assistance would be appreciated.

My situtation is this: I have a 2002 Bravada with AWD and 78000 miles.
When turning fairly sharp to the left or right the rear wheels drag, binding and slowing the vehicle to ahalt. I can go down the road straight without problems.

I took the SUV to my local GM Dealer and their corrective action was to replaced the rear differential lub and the transfer case lub.

After the dealers action I still have the problem.

Question: What should I do next/can I do? I am 65 but I can turn wrenches as that it the way I made my living in the past.

[GusMan]

Do both wheels drag or just one of them during a turn. If it is just one of them, which one locks up? ie: if you make a LH turn, does the RH week lock?

[WOOLUF1952]

Do you have the G80 locking rear? If I remember correctly, some TV'ers used a posi additive to cut down on lock-up of the G80.

[wmhall]

Originally Posted by GusMan

Do both wheels drag or just one of them during a turn. If it is just one of them, which one locks up? ie: if you make a LH turn, does the RH week lock?

Only one wheel locks up and if I am in a left turn the left wheel is the one to lock up.

[wmhall]

Originally Posted by WOOLUF1952

Do you have the G80 locking rear? If I remember correctly, some TV'ers used a posi additive to cut down on lock-up of the G80.

I'm sorry I do not understand G80. I do know that its an AWD system per the owners manuel

[the roadie]

G80 is a code for an automatic locking rear differential carrier - if you have it, the code will be on your glovebox factory build sticker. Like limited slip, but more aggressive.

You can have a G80 with a 2WD, AWD, or 4WD vehicle.

Now please explain what you mean by "lock up." Do you mean it stops turning on the axle?

If so, you might have severe mechanical issues inside the differential, or bearings, or the emergency brake parts.

If you mean the rear end acts as if it's was welded side to side, and one tire scrubs when you make a turn, that's different, and might be a misbehaving G80.

If you got the vehicle up on jackstands, and rotate one rear tire, what does the opposite one do? If it rotates the same way, you have inadvertent locking. If it rotates the opposite direction, that's as expected.

[wmhall]

Originally Posted by the roadie

G80 is a code for an automatic locking rear differential carrier - if you have it, the code will be on your glovebox factory build sticker. Like limited slip, but more aggressive.

You can have a G80 with a 2WD, AWD, or 4WD vehicle.

Now please explain what you mean by "lock up." Do you mean it stops turning on the axle?

If so, you might have severe mechanical issues inside the differential, or bearings, or the emergency brake parts.

If you mean the rear end acts as if it's was welded side to side, and one tire scrubs when you make a turn, that's different, and might be a misbehaving G80.

If you got the vehicle up on jackstands, and rotate one rear tire, what does the opposite one do? If it rotates the same way, you have inadvertent locking. If it rotates the opposite direction, that's as expected.

Checked the glove compartment and I have G80. What I meant by locked up (bad terminology on my part) in making a left turn the right wheel turns normal and the left wheel hops or scrubs in the turn. Once the turn is complete all is normal.

[WOOLUF1952]

Originally Posted by wmhall

Checked the glove compartment and I have G80. What I meant by locked up (bad terminology on my part) in making a left turn the right wheel turns normal and the left wheel hops or scrubs in the turn. Once the turn is complete all is normal.

It will seem normal because both wheels are turning at the same speed, unlike during a turn. The G80 is the likely problem.

[the roadie]

Not a real DIY repair. The dealer will probably want $1000-1400 to replace it. A competent driveline shop might be under $1000, depending on if the clutch packs can be rebuilt. Personally, I've swapped axles for under $500 with a junkyard one with fewer miles.

Didn't the dealer have anything to say when their attempt failed? Pulling the diff cover to look for broken parts should have been the next step, unless you stopped them before they made it undrivable.

[wmhall]

Originally Posted by the roadie

Not a real DIY repair. The dealer will probably want $1000-1400 to replace it. A competent driveline shop might be under $1000, depending on if the clutch packs can be rebuilt. Personally, I've swapped axles for under $500 with a junkyard one with fewer miles.

Didn't the dealer have anything to say when their attempt failed? Pulling the diff cover to look for broken parts should have been the next step, unless you stopped them before they made it undrivable.

Your input is much appreciated. The dealer first changed the fluid in the diff and TF box. Did a test drive and the problem still existed. Then they removed the diff cover to check the assembly and said everything inside looked normal. After completing the two tasks I was told to drive it some and see if the fluid change would make a difference and if not the Diff unit might need replacement. I felt their response was a bit weak (This is what it is or is not)but on the other hand perhaps they were hoping to save me some $$.

Again, thank you.