Final Drive/Rear Diff Oil Type

[NTXC]

Hello everyone,

I’m gearing up for a weekend of wrenching and I want to make sure I have everything I need. I’m working on changing the Haldex fluid, cleaning the pump, and changing the filter.

I figure while I’m back there it’s probably time to replace the final drive/rear diff fluid as well. So the question is: Does the rear diff take the same oil that the bevel/angle gear at the front does?

Appreciate any tips as well. I know I won’t be able to extract all the old fluid. Is this a case of take what you can, fill until it drops from the hole, and call it a day?

Thanks!

[Astro14]

A couple of thoughts:

Any good synthetic 75W90 is fine. I like Mobil 1, mostly because it's about $11 for a quart at my local store.

Get the differential warm (highway drive) before doing this. With warm fluid, you'll get better removal.

Use a vacuum pump/extractor.

A regular hose won't fit. Use a very thin, hard line, like a nylon vacuum line (4mm Mercedes line is what I used), it's the only thing that will get to the bottom of the differential.

Wiggle and move the line to get it fully inserted. If it binds when you pull it out, twist and re-insert just a bit to free it up. Pull too hard, you'll break the line, and then you've added debris to the differential.