124 differential oil leak?

[Chazchuzzlewitt]

hello all,

I was looking under the car the other day and noticed what seemed like some fresh oil stains on the rear differential housing coming from the front where the prop-shaft meets.

Do these tend to leak a bit or should I have it looked at? Is it possible to check the oil level without having a lift?

 

[nicky]

hello all,

I was looking under the car the other day and noticed what seemed like some fresh oil stains on the rear differential housing coming from the front where the prop-shaft meets.

Do these tend to leak a bit or should I have it looked at? Is it possible to check the oil level without having a lift?

It will be the front diff seal that is gone,,this is a common fault..it is not expensive to replace,,all you do is remove the prop shaft,remove the bolt that holds the flange on,remove flange,then remove oil seal and replace with new one,build up again and check oil level..........job done...

 

[tom7035]

hello all,

I was looking under the car the other day and noticed what seemed like some fresh oil stains on the rear differential housing coming from the front where the prop-shaft meets.

Do these tend to leak a bit or should I have it looked at? Is it possible to check the oil level without having a lift?

You have to able to get underneath the car on a level area to properly check the diff oil. In the absence of a lift or pit, a small trolley jack and four axle stands would suffice if you didn't mind working on your back for a short time. You could do the whole job this way (which I suggest you should do if you have fresh oil leaking). As Nicky says, not a difficult job.
Cheers, Tom.

 

[Chazchuzzlewitt]

thanks for the advice... I've not done any work before on the prop shaft- could either of you possibly give me an idiot's guide to this job since it sounds like you've both done it before? Also, what oil should be used to top up?

btw, it's not leaking much- no oil on the ground just some wetness trailing back along the housing from being in the slipstream.

thanks,
Alex

 

[clive williams]

I have an oil leak from the NS output shaft of the diff on my 500E (W124) and I was told not to worry as it waws a common problem and just keep topping it up with LSD oil until it became more problematic.

I have since bought a seal for the output flange and was considering installing it from the outside in as suggested for the prop flange - is this feasible?

Merc 124 500E
Merc T210 320CDI

 

[tom7035]

Alex, a bit of oil dampness is not uncommon at the 'nose' of the final drive unit. It's when you mentioned 'fresh oil' it seemed a bit more urgent. Check the oil level anyway. Filler/level plug is on the left side of the diff. and use Hypoy 90 gear oil.
A long time since I replaced one of these seals, but it should go something like this: Mark the positions of the flanges (propshaft/diff) relative to each other with a dab of tippex or the like so they can be replaced in exactly the same position. Undo the bolts and disconnect the propshaft from the diff. flange. Undo the large nut securing the diff. flange and tap it out of the final drive unit. Dig out the old oil seal with a screwdriver and carefully tap the new one in. Moisten the lip of the seal with oil before refitting the flange into the diff. unit. Can't help I'm afraid with tightening torques, but your dealer/local garage should oblige with these. Also recommend you renew the nuts on the flange bolts.

Clive, the seals on the driveshafts are a bit more complicated. Someone else may wish to advise on these.
Cheers, Tom.

 

[big x]

The Haynes manual covers this. I'd wait a bit and see if it gets worse,half the cars on the road have slight weeps.

adam