all e60 diffs have a drain and fill plug-check more closely

Mine is a 2006 e60 530i

I have checked whole rear end and do not see a fill plug.

There is a drain plug at the bottom rear side of diff but don't see a fill plug anywhere.

Any hints from the wizards?

I checked the BMW pages for the diff and it states lifetime fill. No pictures of a fill plug

That makes no sense.

Any guesses from the wizards?

Just found out it is not a fill plug!

Checked whole top of diff with light and mirror and no fill plug!

Wondering if the item depicted in red circle could be the fill plug?

Mine has only one (1) plug. There is no special drain plug. Used oil needs to be extracted.

I can see how to drain it but then how does one refill it?

If there is a 2-piece drain plug that has a center section like a valve then it can be opened to fill under a little pressure and closed when two liters are forced in.

Where does one find a device like that!

Bentley manual shows fill plug on the back side of the differential about the level of the cross member (you can't see it in the picture above). The drain plug in on the right side at the back and bottom. It could be done away with I suppose. Don't see how they could do away with the fill plug.

Great find, but how in the blazes can you get to it?

The housing is less than an inch from the X-member!

I'll check again with a mirror.

You will have to drop the diff down. I was going to get my diff fluid changed when the shop said they would have to drop it down to gain access to fill it.

That is an involved process.

I will take a look under there again but have designed a fill plug for the drain so none of that action is necessary.

I have to finish the drawing and then send to my machinist

It is which is why I opted to not do the work. Not to mention it would have been a waste of money since I'm getting a Quaife LSD equipped pumpkin installed this Thursday. :dance:

I sure don't know about changing out the rear end as you plan, but I am concerned about getting that fluid changed out!