Differential oil seal leak HELP

[MVK]

I had a small leak on differential oil seal .- Where the big drive shaft enters the differential. I guess its called input differential seal. I avoided repairing it for 2 years now. Its a very small leak. But I think its time to reapir now before a total failure of that seal.

My Qs are

1. The seal is about 10-15 bucks max. But it does not look like DIY job. I am scared to attempt that myself.How much would it cost to replace that as a ball park figure - labor.

2. While they are at it should i replace anything else on that driveline.

3. And can any regular mechanic do it or will i have to take it to a dealer( and leave an arm and leg there).

Anyone knows any good mechanic in queens NY or visinity. PL GIVE ME THE BALL PARK FIG FOR LABOR . This way I dont get taken for a ride.
Thanks
MVK

[engatwork]

If it requires a bunch of machine shop work it could get quite costly and it will be based on if it ran without adequate lubrication for any length of time. Problem is you will want to go ahead and change the flex joints and maybe the center support bearing while you have the driveshaft down. I'm not sure of cost in your area but I imagine it would be easy to drop a grand into a differential/driveshaft rebuild. Try to find a good independent in the area if you don't want to do it yourself. You will probably still need a good machine shop even if you remove/replace yourself. The manual that shows the differntial rebuild has some specific machine shop work detailed in it.
Have you checked on the forum for recommended shops in the area.

[MVK]

Thanks jim.

No i never let the differential run dry. I checked the oil on it about twice and filled it again took abou less than 2 oz each time. So I just need to change the seal.
Now do you think it can be done any cheaper?
Just changing the seal.

MVK

I was going over the old receipts for the 240 last night and have one for a differential front seal replacement done 11/15/01 at a dealer in Bloomington In. The PO paid 863.57 for this service. He had told me the dealer had done lots of work on the car when he was on a trip last year. He's not kidding, same dealer charged him 357.43 plus 55 freight to replace the drivers door seal!

[MVK]

This is outrageous numbers. This just expains why we need non dealer but good MB mechanics. Paying a reasonable amt is I am sure is never a problem with anyone as long as the job is done right. But these 800+ figures are just too high. i am going to check out with my local mechanic how much would he charge.

I still cant sink in those numbers rebooit. Not that i dont believe you so please dont get me wrong.



MVK

The thing I find unbelieve is the $55 freight charge. I bought all the door seals for my car for around $200 from fastlane, shipping was around $12.00. The seal for one door from the dealer was $134.77 + $55 shipping!

[leathermang]

On the 300d my book only covers up to 82... but looking at the blow up you might have gotten lucky... one of the few things on these cars that look straight forward and not over engineered. On the 82 there is one nut holding the universal flange and then the sealing ring....probably need a puller for the flange and may get by with prying the old one out and pressing the new one back on... of course this is after you have disconnected the drive shaft from that universal flange...

[engatwork]

My book shows W123 starting in 1977 but it clearly shows a step called "Replacement of radial sealing ring on drive pinion" - #35-1550. It looks like you should be able to replace it without going all the way through the differential. Does show a pretty elaborate looking puller to remove the drive pinion but doesn't look like anything someone couldn't put together from bolts/puller flange, etc.. You can probably do the job a little more economically. My problem with this type of job is that when I take this stuff apart I want to fix everything that is worn out.

[MVK]

I am so happy for now. I looked at the Benz CD to see how to replace this pinion oil seal. Guess what it explains the whole procedure so nicely AND YOU NOT HAVE TO REMOVE THE THE WHOLE DRIVE SHAFT
( Hayes manual is a little vague about it and says you have to remove the driveshaft)
All you need to do is loosen the a check nut by 2 turn in the front near the transmission, then loosen the nuts on the center bearing clamp, then unflange the shaft at the end( 3 bolts only) towards the differential, now push back the shaft towards the front make sure you tie the shaft with a wire to some heavy solid part on the bottom of the body this way you dont drop the shaft by mistake.
Now after pushing back the shaft anf sliding it off center you have room to remove the nut that holds the flang using the special tool. Once the nut is out, use a puller to pull the flange out. Now you see the pinion oil seal. Pry it out with a screw driver and make sure no portion on it is stuck to the seat. Put the new seal in 9 use the diff oil to lubricate the new seal. Then push it in by slow tapping on it using a big size socket. Push it in until it stops.

Then just put all things back in reverse order. For a home mechanic only problem is no access to lift and the special tool needed to remove the flange nut. But at least you know how easy it is for someone with average mechanical skills and right tools.

Thanks I am VERY HAPPY NOW.

MVK :p

[be459]

MVK,

Read the following post from Steve. Don't toast the bearings.

oil leaking near pinion seal, 87 300D (W124).

David

[MVK]

Thanks david for the tip. I will ask the mechanic to follow that, if he does not have friction wrench.

MVK