Will further damage occur from noisy pinion bearing.

Hello, earlier today i posted a question in regards to my noisy pinion bearing. I didnt word it the way i should have. Will my noisy pinion bearing cause any damage to the rest of my differential system? My mechanic says no. Just thought id ask you guys.. I'm confident it will last for at least a couple more years if i let it be, but i just want to clarify that question. I dont think it will since not much metal will be actually shaving off from the pinion bearing. Just want to hear some opinions from my fellow 1st gen owners

 

The pinion bearing also is shimmed to set pinion gear depth which is part of the gear mesh with the ring gear. So if the bearing wore enough to allow the pinion gear to move/wobble enough it will damage the ring gear also.

Plus, has the differential fluid been checked for proper level, contamination and proper fluid type to make sure it didn't contribute to the bearing failure?

 

@PCJ yes. 2 months ago i heard the noise and did a drain and refill with 75w90 cause i suspected the rear diff making the noise. 3 days ago i took it to the mechanic and they said it was the pinion bearing, they also said the 75 weight i put in is not the factory specs, so i drained and refilled again yesterday with 80w90.

 

It wont damage the rest, not if it's just a whine. Not sure how they are set up, but usually there are shims on a differential for the side bearings. The pinion uses a crush sleeve and can only be used once. Even I as a master tech I wont bother rebuilding one, when you can just find a better rear end.

 

If pinion bearing failure has begun (rumbling, not whine), two years additional life is very optimistic in my opinion. Remaining life may be limited to weeks or months. Metal is not shaved off failing bearings...bearings fail from metal spalling off the rolling elements and races, with the metallic debris inside the bearing accelerating the process.

@zombie may have the best plan: Drive to destruction, or until noise is unbearable (whichever comes first), then replace with a used differential.

 

@zombie Okay thanks. So eventually whenever i feel like fixing the noise i should just buy a whole new/used differential housing pretty much? Ill get to that next year probably.

 

Crush sleeve sets bearing preload/rolling torque not pinion gear depth. Shims under pinion bearing set pinion depth and the carrier side bearing shims set ring gear position and carrier bearing preload.

 

@JohnLakeman thanks for the clarification between a failing one and a noisy one. Mine is just whining at this point, so I'm good to go for a little while longer

 

Sorry for misinterpreting the problem. I believe the whine may actually be from out-of-spec gear contact, which can result from normal pinion bearing wear as the techs have said. Bearings that are making noise are well down a short failure road. Best of luck.

 

I never said anything about the sleeve setting pinion depth.

 

So if it's just a whine, that's all it is, there will be no shavings unless it starts to grind. For example, I have changed thousand of wheel bearing in my time. Just for a whining noise, and when you remove it it looks just fine. Imports mostly. Chevy will go from a whine to a grind very quickly.

 

I also just gave minor info on what's in the rear end to defer you from trying to fix it. So as you can see it's a complicated thing.

 

Must have misunderstood what you wrote. My apologies.

 

It's all good.