Question with front and rear oil seal and diff seal

[erickmarciano]

Hi guys got 3 questions
The oil pan is off
1- for the front seal should I install the race and seal before I bolt the oil pan?
2- my rear seal is leaking does the top rear seal sit in oil or just slash oil from the pan?dont really want to remove the crank unless I have to.
3-I  see a puddle of oil where the rear pinion seal is on the floor.
I cleaned the area well and see traces of oil on the floor tunnel right above the pinion seal .with the car on the lift
It does not leak . Can it leak only when oil is hot?
Thanks
Erick

[ja17]

Hello Eric,

 May be a bit easier with the pan off.  The rear of the crankshaft is not submerged in oil.  replacement of the lower half can make enough difference to keep from removing the crankshaft.

The rear pinion seal is the usual culprit for rear diff leakage, as long as the axle boot is ok. The rear diff oil fills only half of the housing. With the axles hanging down from a lift, the oil moves to the alxe tubes. Loss of oil from the pinion seal is minimal and usually not a cause of serious oil loss.

[Ulf]

I'm just reviving this topic as I too have discovered a leaking rear diff - to the point where I need to place a piece of cardboard underneath the car. Is this the pinion seal you mentioned?
http://www.theslshop.com/mercedes-benz-w113-pagoda-pinion-seal-ring-0049975646.html

Thanks in advance

Ulf

[rutger kohler]

Hi, although the pinion oil seal won't leak at rest, if you drive the car for some distance and it is leaking, the oil can blow back onto the diff casing itself and then drip down in your garage later, however this won't be a lot.  I have changed my pinion seal some time ago and the diff still leaks so it looks like a major for me, because I have not heard of many people have success with the split type rubber bellws replacement.  be delighted to hear from anyone who is happy with this fix.

[Ulf]

That might be my issue as it is getting worse and worse, will look into it this weekend :-)

[Shvegel]

Another thing to check is the vent for the rear diff.  Due to the nature of the rear seals air can easily be sucked in as the diff cools but if the vent is clogged the diff can pressurize as it heats up.  Due to the rubber boot on the rear I would assume that this isn't as big a problem as a solid diff but it's worth a look.  It is just to the left of center(Side away from the boot) at the top.

[rutger kohler]

Hi, thanks for that, well worth checking.  I already did that but would recommend it to others who haven't.