Front Diff Fluid Capacity

LA02MAX · #1 03-28-2022, 11:55 AM

I've searched and searched on this topic, and haven't found any definitive information for the E53 chassis. Most people seem to fill these until the fluid level is at the bottom of the fill plug. However, there are a few threads on the E70 forums that show a snapshot of the fill process, and it expressively states to not fill until fluid exist the fill hole. Instead, it should be filled with 600 ml of fluid.

I'm digging through the TIS application and I can't find a similar statement for the E53. What I did find is that the new filling volume is 700 ml and oil change 600 ml.

Does anyone know what the official fill procedure recommends? I changed the front diff fluid and filled it until it was level with the bottom of the fill hole. This definitely took more than 600 ml of fluid. ~1000 miles later, my front differential pinion bearing blew. I just got a brand new OEM differential, and I want to make sure I don't mess this one up. I'm leaning toward following the TIS capacity and measuring out 700 ml (for a new diff) and calling it a day. Thanks!

Bdc101 · #2 03-28-2022, 12:35 PM

I filled mine up until it came out of the fill hole a couple of months ago when I did it, so if that's not the right thing to do, then I would love to know!

SirHiss · #3 03-28-2022, 01:00 PM

Mr Pelican says to fill until it comes out of the hole.

https://www.pelicanparts.com/techart...eplacement.htm

oldskewel · #4 03-28-2022, 01:17 PM

From my notes, on my 2001 3.0i, I put in about 700 ml of 75w90 GL-5 synthetic gear oil. Of course I filled it to the bottom of the fill plug hole. My 700 ml estimate is based on how much was left in the 1 liter bottle.

It seems fairly ridiculous if it were designed to be filled not up to that point, considering they can put the fill plug anywhere they want. Of course there will be a tolerance, such as at that level or 5 mm lower. Overfilling beyond that level (tilted car, putting the plug in while the excess is draining out, etc.) could cause problems.

I did that when I first got this car, 33k miles ago and nothing has blown up yet. Well at least the differential has not blown up.

Sorry to hear about your problem, and good luck.

And BTW, I think in general the front diffs on these cars tend to be more neglected than the rear diffs. When changing all the fluids on mine after first getting it (not trusting that anything was good), I noticed the rear fluid was not bad, but the front was looking original at 169k miles. Now at about 203k, both diffs and the AT are original and doing very well. I think the reason for the front diff neglect is the need to remove the stiffening plate for access - more easily skipped than the rear diff.

Bdc101 · #5 03-28-2022, 02:02 PM

Quote:

Originally Posted by oldskewel

And BTW, I think in general the front diffs on these cars tend to be more neglected than the rear diffs. When changing all the fluids on mine after first getting it (not trusting that anything was good), I noticed the rear fluid was not bad, but the front was looking original at 169k miles. Now at about 203k, both diffs and the AT are original and doing very well. I think the reason for the front diff neglect is the need to remove the stiffening plate for access - more easily skipped than the rear diff.

Definitely. The stiffening plate is a PITA. It's not really that hard to take off, but it's always absolutely filthy, and then you have to wade into the argument of whether to spend the money replacing TTY bolts or not.

LA02MAX · #6 03-28-2022, 02:06 PM

Quote:

Originally Posted by Bdc101

Definitely. The stiffening plate is a PITA. It's not really that hard to take off, but it's always absolutely filthy, and then you have to wade into the argument of whether to spend the money replacing TTY bolts or not.

Yeah, it's never fun... The TTY bolts + the fact that it's a bolt and nut that you have to wrestle with. lol. But I dropped the entire subframe out of the car, cleaned up all my valve cover leak mess, replaced the diff, replaced the motor mounts, and while I had the subframe out, I replaced the upper and lower oil pan gaskets and other associated gaskets/O-rings. So at least, in this case, removing the stiffening plate was a small part of the job

andrewwynn · #7 03-28-2022, 01:47 PM

TIS for e53.

LA02MAX · #8 03-28-2022, 01:49 PM

Quote:

Originally Posted by andrewwynn

TIS for e53.

Thank you so much! No clue how you found that, but I'm very grateful! I suppose my previous diff was just close to going boom and it was just a coincidence.

LA02MAX · #9 03-28-2022, 01:48 PM

I did see the pelican parts how-to, and I was mainly questioning the validity of it.

I completely agree about the fill plug position, but sometimes BMW does some crazy stuff. And the fact is, the E70 diff looks mighty similar to the E53 (at least the 3.91 in my 4.8is...). And the E70 instructions are very clear that it shouldn't be filled until the fill plug. As is the procedure for the rear diff on my G01 X3. Stupid, but that's what's throwing a wrench in my thought process.

If it took 700 ml to fill it to to the fill hole, that would be great. I just seem to remember it taking over 1 liter to fill mine for some reason. And the whole experience of the differential blowing up shortly thereafter has me on edge. haha. That $1600 part was a tough pill to swallow on an unscheduled repair. I wish I could find the official TIS procedure for this, but for one reason or another I'm having serious trouble.

andrewwynn · #10 03-28-2022, 01:52 PM

The TIS also says the exact same for e70 diff. Fill to the bottom of the fill port. The text and photo appear to be copy and paste identical. Where did the "very clear" 600ml directions originate?