'98 E300D differential Seal
 

Hello All,

The front (input) seal is badly leaking. can someone advise to the "do ability" of replacing that seal. I see it in the catalog PN: 024-997-99-47-M104

Special Tools? Tips? Tricks?

Any and all advice welcome. Thanks

I do not have an answer for you as I have never tackled it, but I ended up having a leak in mine and the thing started whining real bad then grinding about 2 hours away from home. Ended up getting a NOS one from a buddy of mine in the UK. It had the proper gear ratio for the diesel but was for a E320 so I had to swap the input flange on it. Since it was brand new I just tightened the bolt back to the same spot it was and it turned out fine but I think you have to get it in the exact right spot using some sort of special measuring tool in order to do it the right way.

http://www.peachparts.com/shopforum/diesel-discussion/344307-w201-differential-refresh-thread.html

This is for a 201 but the diff is similar in a 210.

Hmm looks more complicated than I hoped it could be. Maybe better to try to find a not leaking used diff. Consider me on the hunt.

Sometimes you have to jump in and just do things no fear. :)

I replaced my diff in my w210 but at 518k it was pretty worm out. Mostly from the P.O. running it low on oil and a nasty whine which eventually lead to the diff locking up at 5mph and me buying it for $250

Differentials aren't as scary as one would lead you to believe. I've assisted in rebuilding one on a jeep, but the principle is the same. If you decide to do it, I can help as far as questions go with any issues even though you're not rebuilding yours but resealing.

Thanks all. Jake: To expand on the situation for a little more clarity. The '98 is part of the benz fleet that i maintain/repair. It belongs to a friend of mines business serving as a company car for his sales person. So, timely repair and as much of a guaranteed fix is what i'm shooting for.

The way i see it right now... just replacing the differential saves time and gives us a better shot at getting it right the first time.

Also, it wasn't just leaking. It did have some kind of failure that lead to them having to get towed home. He described a sudden feeling of dragging, smoke coming from the diff, and apparently red hot metal on some part of the diff. So, i'm fearing that there was probably some other damage beyond just the leaking. Although, after they got it back to the shop they were able to move the car with seemingly no problem.

it sounds like leaking caused a lot of heat and metal damage on the gears. I didn't know that whole story. like you said at that point. your best bet is to repLace the differential.

Right.. I'm leaning that way for sure. Working on trying to track one down now. I see a few on the bay. Looks like 3:07 gears for the turbo diesel? i wonder if gassers had the same diff gears. And i also wonder if a w124 diesel differential would work.. long shot i'm sure but i do have one of those sitting on the floor and one picture that im looking at looks very similar

3.46 ratio for the turbo diesels 97 to 99. I'm not sure if a w124 ratio would work

My rear diff was weeping just a little bit around 135k. A new seal wasn't available so we removed the old seal and replaced it with a black RTV paste (I'm not sure if that's the correct name). Anyway, I'm at 246k miles and it hasn't show any signs of weeping again. I ran a Blackstone lab report on the oil at 185k and it passed with flying colors.