Rear Diff Not Locking Up

Dieseltruckin2001 · March 12, 2009

Ok, so I had to stop and use 4wd to take off uphill from a stop sign today(wet pavement). I have a 2004 Z71 with the G80 locker. I went to a little hill and tried to climb it in 2wd and watched my rear tires. I can not get the rear end to lock up and turn both tires going forward or backward. There is no noise coming from the rear end and never had a "pop" or anything to indicate something broke. I changed the fluid in the rear end a while back but put synthetic fluid with no addatives (as per GM tech's) back in. Any sugestions before I spend who knows how much taking it to the dealer?

Stevens03 · March 12, 2009

How fast where you spinning the tires, they lock at low speed. If you brake a little while putting the gas on, they should lock up pretty quick.

Steven

Dieseltruckin2001 · March 12, 2009

How fast where you spinning the tires, they lock at low speed. If you brake a little while putting the gas on, they should lock up pretty quick.

Steven

I tried it very slow, then with one foot on the brake, and then I floored it. Nothing works. I even tried it in 4wd to see if that made a difference, nothing.

silveradobobby · March 12, 2009

How fast where you spinning the tires, they lock at low speed. If you brake a little while putting the gas on, they should lock up pretty quick.

Steven

I tried it very slow, then with one foot on the brake, and then I floored it. Nothing works. I even tried it in 4wd to see if that made a difference, nothing.

Sounds like the gov lock is broken, some times the make a ratching noise and some times they dont if its broke it wont lock the diff in not even a pop!

Dieseltruckin2001 · March 12, 2009

How fast where you spinning the tires, they lock at low speed. If you brake a little while putting the gas on, they should lock up pretty quick.

Steven

I tried it very slow, then with one foot on the brake, and then I floored it. Nothing works. I even tried it in 4wd to see if that made a difference, nothing.

Sounds like the gov lock is broken, some times the make a ratching noise and some times they dont if its broke it wont lock the diff in not even a pop!

Ok, so if that's the case. How do I find out what rear end the truck has so I can replace the locker with something like a detroit?

Dieseltruckin2001 · April 13, 2009

Ok, I give up. What is a good replacement for the G80 locker in the Z71? It's all stock, so just something of at least equal traction but something that will hold up to normal use. Also, cost effective, since I'm a victim of the "good economy" and was recently laid off from work.

mr_bots · March 12, 2009

Do you have traction control? That might cut engine power before there's enough of a difference between wheel speeds for it to lock.

Dieseltruckin2001 · March 13, 2009

Do you have traction control? That might cut engine power before there's enough of a difference between wheel speeds for it to lock.

No, no traction control that I know of. I can make one tire stand still and the other one turn as fast as I want. It's acting exactly like a completely open diff. I might tear into it in the next day or two and look for any metal shavings or anything broke inside the housing.

Alljackedup408 · March 14, 2009

the g80 will break before an axle.. built in safety so you dont shoot an axle out =0... if youre looking for a detroit.. ive got one in my 99 silverado.. but i swapped a dynatrac dana 60 into it... the only bad is the locker doesnt like to disengage around corners.. really when its wet.. so.. it chatters some times... just a heads up.. but its bullet proof.

Alljackedup408 · April 13, 2009

you could try using a powertrax made by richmond http://www.richmondgear.com/powertrax/noslip.html ... dont know what ur budget is... this unit is about 125 bucks cheaper than a detroit. Another idea is go down to a junk yard.. and remove a locker from a wrecked truck.

silveradobobby · March 13, 2009

Do you have traction control? That might cut engine power before there's enough of a difference between wheel speeds for it to lock.

No, no traction control that I know of. I can make one tire stand still and the other one turn as fast as I want. It's acting exactly like a completely open diff. I might tear into it in the next day or two and look for any metal shavings or anything broke inside the housing.

Yep sounds like the gov control is broken or the teeth are striped!

Dieseltruckin2001 · March 16, 2009

Yea, I like a detroit, but I'll have to wait on it for now, funds are a little short. Had one in a jeep I used to have and it was the same way, no gas and coasting around corners and it would chatter. But like you say, bullet proof, lol.