Diff seeping oil

[Fender2004]

Where the drive shaft comes out of the diff there is a oil seeping, not a lot, not even to drip in the floor.

My question is can I just disconnect the drive shaft to give me access to the seal on the diff or will the diff have to be removed completely to replace the seal?

Will I need a puller to remove the output flange, or is it just kept in the a big nut?

Thanks for any help

[Southernboy]

Detach the propshaft from the diff. You will see a large nut which has a "locking washer", you will need to bend the washer away from the nut. You will need to prevent the shaft turning while undoing the nut. Make aligning marks on the nut and flange to replace the flange as it was. Once the nut is removed, you will need to pull out the input flange. You may need a puller. Be prepared to catch oil !!
Once you have removed the input flange, check the shaft for excessive wear. If it's worn - replace it. (Remove the rubber dust cover) If not....Pry out the shaft seal without damaging / scratching any surfaces. Dip the new seal in oil and drive it in - squarely!! Suggest you replace the dust cover at the same time. Lightly lube the input shaft and replace aligning with your marks made earlier. Tighten the large nut to as close to the original marks you made before undoing it so it is about as tight as it was before. Drain and refill the diff with new oil to spec for your car.
Hope that helps.

[Fender2004]

Thanks for that Southernboy but my leak is where the drive shaft is not the propshaft as you discribe.
Is it the same sort of procedure?

[Southernboy]

Are you referring to one of the axle shafts to the wheel?

[Fender2004]

Yes the shaft that goes from the diff to the wheel.
With the leak at the diff

[Southernboy]

Oh, and top up the diff oil again afterwards. But since you're going to lose some oil, and you'll need clean diff oil to dip the new seals into, you may as well drain and replace. I reckon do both sides, if one side is gone, the other won't be far behind. Make sure you check the flange shaft which goes into the diff to make sure they aren't worn excessively, otherwise you'll be doing this job again soon.

[c_w]

Yes you need to undo the driveshaft using a star socket. The inner half shaft just lever out with big screw driver. The you can see the oil seals.

Drain the oil first and replace as suggested above.

[Fender2004]

Thanks for all the advice guys

[Andyboy]

When doing these, make life 10 times easier by undoing the 13mm bolts and removing the side plate with the seal. Clean it up and replace the seal with the side plate on the bench. The diff won't fall out or anything! Fit the seal with a big socket and a rubber mallet, soaking the seal in oil first.

[Fender2004]

When doing these, make life 10 times easier by undoing the 13mm bolts and removing the side plate with the seal. Clean it up and replace the seal with the side plate on the bench. The diff won't fall out or anything! Fit the seal with a big socket and a rubber mallet, soaking the seal in oil first.

Cheers thanks for that I think I might just replace the seal this way
Does sound easier replacing the seal on the bench rather than under the car.

[wella_fella]

Hi,

I also have a small amount of oil seeping from the diff.

Does anyone have a guide for replacing the seals or even just some help to identify the part number on real oem?

[wella_fella]

Fender2004 have you replaced your seals yet?

if so can you let me know which seals i need to replace:

http://www.realoem.com/bmw/showparts.do ... g=33&fg=10

is it one of theses?

Sorry i think im slightly confused!

[Fender2004]

Fender2004 have you replaced your seals yet?

if so can you let me know which seals i need to replace:

http://www.realoem.com/bmw/showparts.do ... g=33&fg=10

is it one of theses?

Sorry i think im slightly confused!

Sorry to tell you I'm just gathering information and I'm planning on doing the seal replacement when I take the car off the road in the winter.
I think the seal you need is number 6. Plus should the O ring be replaced as they can' t be that expensive?