I have a set of large Allen keys as well as a 1/2" hex bit socket set. I removed the filler and drain once before, but that may have been on my 107, which is so similar, I get them mixed up!

Regarding the washer - From what I recall, one of the plugs has a washer and one is a tapered thread and has no washer.

I have car up quite high, but couldn't budge the filler plug. Afraid I might push it off the jack stands! Would be easier on a hoist. Maybe some heat would help.

PS: Those upper diff plate bolts are in a tight space. I never tried getting a socket in there. But do recall in axle DIYs that it was suggested to lower the diff to get at those bolts. Is that not required?

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Graham
85 300D,72 350SL, 98 E320, Outback 2.5

The job is best done with a floor jack under the differential. That way, you can lower the differential to remove the cover and clips, then raise it to improve the axle geometry when it's time to remove the axle shafts. Then you can lower it when you replace the shaft seals. Then raise it to install the shafts. Lower to replace the cover. Raise it to reinstall the mount. None of which is particularly difficult.

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When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

Graham ;

I use (ALWAYS ! 3 ton safety stands so shoving the car off them isn't a worry .

I took a really hard push with my feet to break the filler plug loose .

The filler plug has n aluminum gasket, the drain plug is a taper thread .

When doing the drive axles on a W123 (I've not yet done a W126) you remove the rear wheels first, then undo the 13MM ATF bolt and push the axle inwards, it'll barely clear the outer suspension .

Then you undo the top two diffy cover bolts and then the 15MM ATF bolts and the cover comes right off .

I normally use two crossed drifts and a mallet to pop the snap rings loose, the last one went flying over my shoulder so I bought a spring hook tool at a Motocycle supply shop, it should work .

Yes, you're going to have to raise up the diffy after you've finished installing the new axles .

Remember to clean the diffy cover's mating surfaces HOSPITAL CLEAN using small wire brushes and alcohol, then smear a tiny bead of your favorite sealant just before you re install the cover .

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-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better