RudeXJ

Hey guys,

Just swapped in a used C8.25 and been grappling with some weird noises from the rear end.

The first happens around 50mph, when I let off the gas, I get a short burst of grinding noises, like metal on metal, its almost as if there is play in there and when torque is released, it moves.
The second happens from about 60mph - deep droning noise when foots on the gas, and grinding noise when I let off.

Check out a few video's I've shot - a couple with the jeep on jack stands and one driving.


I've taken the cover off and all looks fine, not missing any teeth, however I noticed the spider gears were binding, so I took them out and found quite a bit of wear on the cross pin and c clips - this normal?
Replaced the spiders and cross pin, they turn fine now, but the noise is still there.

I'm guessing carrier bearings? or is this a full rebuild?

Any advice greatly appreciated.

tech

Sounds like mine when I had a bad pinon bearing you can'pinon and ct see it . you will need to remove the pinon and look at the bearings .

RudeXJ

So that was my initial thought, however from research I’ve done nearly all bad pinion references, including the FSM indicate a high pitched whirring noise as a bad pinion bearing. Also I’ve tugged really hard at the yoke and there seems to be no play whatsoever which is confusing.

tech

Mine had no play so I thought it was the carrier bearings , so I ordered the carrier bearings 1st. and it ended up being the pinon bearing so I changed them all .

RudeXJ

Yeah I guess if you’re doing carrier might as well do all.
well thanks for the confirmation, I guess that’s what I was looking for.
Did you do it yourself? Is it quite simple? I’m a relative wrenching novice, but not scared to try new things. There seems to be a lot of info online

tech

I did it my self there are videos on you tube you can see how to do it . I did have to cut off the larger bearing on the pinon with my dremel , to install it I just heated it up a bit and it will drop on just reuse the shim on the pinon .also cut off the carrier bearings and for the shims on the carrier just put them back in the same place they came out of so the only thing that changes is the bearing and you should be good .

RudeXJ

Thanks man, yeah there is one hour long YouTube vid in particular that has all the info you need...it’s really not rocket science. A friend has a really bearing puller, so hopefully I won’t have to cut...that scared me. Will be sure to put all shims back where I found them, thanks

tech

They cut easy with a small cut wheel on a dremel and I think I only used 1 maybe 2 cut off wheels . just had to clean up all the parts after that . my bearing puller didn't work so I just cut them almost all the way though then used a chisel to break the bearing race .