cb3325

When I make a right turn in my 2007 Suburban the right rear wheel seems to lock up and cause the car to studder on only right turns. I was told it was a rear diff problem. Is there a way to unlock the problem? would changing diff fluid do anything or do I have to change rear diff entirely?

someotherguy

Do you have RPO code G80 on your option code (SPID) label in the glovebox? If so, that's the factory locker, Eaton Gov-Loc. Has the lube ever been changed? Someone may have put in some "posi additive" which is not recommended for this unit, and there's a TSB out from GM saying it can cause chatter and improper operation - procedure is to flush out that lube and replace with factory recommended lube. See your manual, though it's likely 75W90 synthetic.

Richard

cb3325

I have had the truck since 2010. I have put 125k miles on it bit have never changed the diff fluid. Could that be the cause of the rear diff locking? I am not great w cars. There should be a way to unlock the gears (at a certain speed or something.). What do you mean by the option code G80? I was told that I have an Eaton G80 rear diff.

someotherguy

Look inside your glovebox for a sticker with a bunch of 3 digit codes. If G80 is on there you have the Eaton Gov-Loc.

If you've never changed the fluid, the chances someone before you between 2007-2010 are hit or miss, then also hit or miss if they put the wrong stuff in there.

Old fluid, as long as it's the correct stuff, will not likely be the cause of your problem...but you can replace it as relatively cheap insurance just to see if it helps. I'd also wait for other opinions here before jumping on it.

Richard