I just bought a 2002 2500 2wd that had horrible brakes. While changing out the passenger side rear rotor, the inside of the rotor and e-brake shoes were covered in what smelled like gear oil. I don't know anything about axles so I'm not really sure what I am looking for as far as a fix. I'd appreciate any direction anyone has. I don't hear any hum or noise from the rear, so this was kind of a surprise. The other side was 100% dry like I imagine it should be.

 

If it is thick it is gear oil, you have a bad axle seal. I NEEDS to be fixed or you will grenade.

 

Yep. Check the oil level in the diff and make sure it is up enough so you don't blow the rear. Make sure that the fluid is gear oil and not brake fluid. If the wheel cylinder is leaking it will leak brake fluid. Don't do the brakes until you fix the leak- once the shoes are soaked they're useless. If you do the seal may want to consider doing both since you're already going to have 1 axle out. Also check the bearings.

 

It was the seal - super easy fix. All I had to do was pull the 8 bolts once the wheel and brakes were off, and the axle slid right out. Removed a 2 9/16" nut and locking clip, removed the hub, and there was the bad seal in the back.

 

I love full floating differentials. Makes life SO much easier.