Tools needed:

14mm Hex - 1/2" drive
1/2" drive Ratchet
Transfer Pump
Jack Stands/Ramps
Low profile floor jack

Drive the car around for a while to warm up the rear diff oil.

Then lift the car and make it level.
Click here to read the entire tutorial

Thanks for the reply, ill make sure to use full synthetic only

Is this the right part # for the plug ? 33117525064 I'm guessing it's the same for all e90s ( I have a 2006 330i)

Thanks!

Nice write up and thanks for sharing but its a bit scary in my opinion. I wonder how much a Indy shop or at the dealer charges for this kind of job.

Thank you very much!

GoRomeo, I just finished this job yesterday for the first time and the only scary part is jacking up the car. It's actually quite easy to do this given you have the right tools and have turned a wrench before. I recommend having a friend around to assist with putting the car on jack stands though.

Great write up OP.

Took longer to jack up the car and put on jackstands than the actual change did. Thanks for the DIY guide. Such a simple procedure. I got about 1.5 quarts out/in.

Thanks OP! Its very nice just having a tools list to help, had to go to 2 different shops to find a 14mm hex socket haha... Thanks again!

Tried doing this today but couldn't get the drain plug off, seems like it is stuck. How did you guys take it off?

My car is on stands waiting for a motor mount to come in so I may do this in the meantime.

Mike, you and I have the exact same car (06 325i) Let me know how it goes with getting that pesky differential oil plug off ...

What size bar/ratchet are you using? Might help if you use a breaker bar...

I have a 3/8" ratchet that is about a foot long, typical handtool size.
Might have to go out and get a breaker bar then ...

I had to use a breaker bar on my '06, it was in way tighter than the torque spec, and it deformed the metal (aluminum) around the socket of the plug. I was glad I had a new one to replace it with.

Just did this today and was relatively easy. Wish I had a better way to hold the bottle still while filling it. Almost tipped over several times!! Both old and new fluids smelled like sh*t

Thanks for the article i baes most of my work on it. I over tensioned the fill plug and now the outside ring of the plug snapped off and i need a new plug and crusher washer. Should i get a new plug or seal the outside with silicone?

You can seal it with silicone until your next change with a new plug/seal ring. I don't think it'd be a problem.

get a new plug, any dealer should have them
these plugs dont have washers, they all come with a oring attached to them

Also did this one over the weekend and tried using an oil suction gun rather than a transfer pump, and that made it tough to get all of the fluid out because the drain hole is angled up and you need to get about 3 or 4" below that level. Sure, I could've run out to the store and bought more hose or an elbow but I made due:

Took an old metal tent stake and bent it like a "C" and inserted that into the tubing. The stake wasn't going to fall out but I cable tied one bend for insurance. I was able to suck out all the nasty, old gear oil in 3 pumps using that setup.

Putting it back in was also a little tricky since the suction gun doesn't evacuate all the fluid in the tubing if it's facing up at an angle and fighting gravity. I would recommend a transfer pump for this job unless you just like making things difficult.

Last note, I agree with a previous poster that the plug was a lot harder to get off than the 60 Nm I applied to torque it back on. Maybe it was just from 6 years of not being opened?

Great DIY, but yes, dangerous setup no doubt. Get you some $25-35 jack stands and use the hydraulic jack if you want in the middle of the car just as an added support. I usually just snug it up after the car is on all 4 jack stands.

Did mine today, the old stuff at 76k looked fine, probably wasn't necessary. Have Redline 75w90 in there now, wouldn't expect to do this again for at least 100k miles if that.

Well, I finally got around to doing this at 92k... and my 14mm hex socket just spins around, the bolt is way bigger than that. WTF. Nothing worse than prepping for a job and realizing you wasted 30 minutes because you have the wrong (albeit suggested) part...

I recently developed a howling sound emitting which I am sure it's the differential . I looked under and I see dried oil dirt residue on the bottom part if the cover and to the front (not back as you would think it would ). Could it be leaking ? I am getting me a socket to check fluid as it could be low and this is why the sound? Any ideas ? Thoughts?