UPDATE...


Just took this truck to dealer again for oil change and some other items.
One being rear diff noise. Tech advises its the pinion bearings now. They plan to replace them, and the Carrier bearings (AGAIN) as a precaution.
I asked about the wheel bearings also since they would have been contaminated by the same diff grease as the other two sets... Waiting to hear back.
I did ask Tech about rear diff grounding and he did not know of any or that any of them had it since there were no electronics in the rear diff. ????


SOMETHING IS NOT RIGHT!!!

 

The grounding issue in some large trucks is a result of static electricity buildup on long hauls and associated arcing causing pitting of bearing surfaces and premature failure. Kind of a long shot here, probably something else going on.

 

Further update.


Picked up truck this AM. Tech replaced Pinion Bearings, Carrier Bearings, and Wheel Bearings under parts warranty.


I took a look at all the bearings and the wheel bearings did show some wear expected with 97K miles. Pinion bearings showed a little more wear. The worst wear was in the Carrier bearings AGAIN.


I asked the tech a couple of general questions such as "What lash did you set this up at?" He was spot on with .08-.012. Also asked "What could be causing this? Mis alignment from factory, or what?" Tech said he looked at and inspected it for alignment (some how) and the rear diff tubes did not show bent up, down, fwd, or back.


Im not sure what is going on but we will see...

 

Usually consistant bearing failure results from either improper installation, too tight, which also wrecks the ring gear or not cleaning the housing of steel chips. UR at the point where a different axle/differential might be wisest choice. These promlems usually begin with the pinion depth being set wrong which magnifies by trying to make up for it at differential carrier instal and usually ends up noisy but not the bearings busted up like total bearing failure would do.

 

Thanks for the reply.


Im told they totally flushed the rear diff internals, axle tubes and all. They did replace all the bearings as I inspected them after the fact.


We will see.