Just wanted to know anyone has any info on the G80 rear differential feeling like it is locking up on some turns, Sort of a shutter then it is ok for miles , mostly left turns with a load. This just started at 41000 miles , the gear lube was changed at 5k miles and again at 25k, and at 36k before a 4k towing trip out west - Mobile 1 75-90. I do a lot of towing . I understand there is no additive needed other then 75-90 in this Differential. Thanks in advance for any Help

Just wanted to know anyone has any info on the G80 rear differential feeling like it is locking up on some turns, Sort of a shutter then it is ok for miles , mostly left turns with a load. This just started at 41000 miles , the gear lube was changed at 5k miles and again at 25k, and at 36k before a 4k towing trip out west - Mobile 1 75-90. I do a lot of towing . I understand there is no additive needed other then 75-90 in this Differential. Thanks in advance for any Help

As I understand it, many here run that Mobil 1 gear oil with no additional LS additives and have no trouble. I would check your fluid level and make sure it is at the proper level.

I have also read a few threads where members that tow heavy and frequently have recommended the 75W-140 Mobil 1 gear oil. You may want to do a search on that.

I also remember one "chatter" threads/post with G80, but that truck owner was using Amsoil.

Good luck.

we just pull the cover and flush all the fluid out.

I am having that same prob. right now! Does anyone have a fix? Just changed my rear diff fluid with AMSOIL as well:rolleyes: is that the problem?

I agree with jfarr, I would change to Mobil 1 75-140 gear oil. The owners manual recommends this oil viscosity when the truck is used for heavy towing. I have ~195k miles on my truck w/ the G80 and have not had any issues.

Good luck.

Mark

I have this happen time to time. It has been my expierience with a locking diff, when it gets hot it sometimes tends to get sticky but goes away within just a few seconds. But changing gear oil wouldn't hurt.

Same problem here. Dealer changed fluid 2x. Dealer is rebuilding my axle now. Only 13K miles on it. Feels like my carrier bearing or something in the driveshaft is bad too. It shutters when you accelerate from a stop. It engages both sides of the axle when I turn (4-5 times per week).

I am having that same prob. right now! Does anyone have a fix? Just changed my rear diff fluid with AMSOIL as well:rolleyes: is that the problem?

I don't think the Amsoil is the problem, I'm running the Amsoil severe gear synthetic with no issues.