Rear Differential Flush due to lack of maintenance?

[BamaRaised]

Hi there, I am currently doing maintenance on my moms 2010 Eddie Bauer 4.0. When I drained the rear differential I caught some of the oil, and I can tell it is way past it's service life, it has a gray color to it and seems to have lost a good deal of lubricity. There is some sludge build up on the end of the drain plug as well. Rather than just refilling it with gear oil and calling it a day I would prefer to give it a proper flush if possible. Does anyone know of a good way to go about doing this? I had considered removing the differential cover like I did on the front, but it seems like it could possibly turn into a nightmare given how everything is set up. If anyone has any suggestions on how I could do a proper flush it would be greatly appreciated. Thanks in advance!

P.S. There isn't any noise coming from the differential or anything like that. I just want to try to extend the life of it as much as possible given the lack of maintenance it has received.

 

[Rcflyer330]

While you probally don't need to do anything but refill it. If it was my car and it bothered me I would refill it and drive it for a few thousand miles (1 engine oil change interval) then drain and refill again. Also check the axle seals I have had problems with them.

 

[94Eddie]

I second just doing a drain and fill. Also, what you might think is sludge on the drain plug is just small metal particles caught by the magnetic tip. This is normal wear over time and doesn't mean there is a large amount of sludge in the differential.

 

[michael loibl]

I also recommend just refilling it, and then doing another drain and refill later, but I’d wait more than til the next engine oil change.

 

[BamaRaised]

I appreciate the advice fellas. I ended up just refilling it and i'll check it out within the next couple of oil changes.

 

[Blackexplorer06]

I did mine at 150,000 miles. It was pretty clean. Refilled with Valvoline full syn.