Lately under moderate acceleration I can feel a grinding vibration. Today it started a vibration at highway speeds.
Tonight I pulled the plug on the rear differential , oil puked out like it was way overfull and it looks like a thick silver paint.
I could be wrong but I think my rear is going out with only 5500 miles on the odo.
What do you all think.

Mooseman

 

"silver paint" ? is it cloudy, that could mean that water got in there, might want to check the condition of the vent hose. I'm sure others here that are more knowledgable than myself can help

 

Its not at all cloudy. Just looks like thick silver paint.
mooseman

 

It may have been overfilled from the factory. I'd just change it out and put in a good GL-5 rated synthetic gear oil and see what it does.

Mine had a silver paint look to it too. These AAM Axles start life with very very tight tolerances. I have heard (from a guy on here who knows a guy who works for AAM)....that these axles will get up to like 650 degrees during break-in. Once broke in...they will run great. Just dump that old fluid and put in some new.

Personally, I use Mobil 1 75w90. But there are plenty of good brands out there.

 

A lot of that silver is also the gear marking compound used when setting up the axle.

 

The dealer says everything is fine and blame any vibrations on my new tires.
It only vibrates under HEAVY acceleration and it started a week before I installed the tires so I think that rules the tires out. They also said everything in the drivetrain including silver oil is also within spec.
OH WELL ill runer till she blows and then fix whatever breaks.
Mooseman