Differential advice please

[Stevie A]

I have a 190E with a slight differential oil leak that I noticed today when changing spark plugs and engine oil etc, then had a look about the car.

When looking from the boot area below the back of the car, the oil leak appears to be coming from the bottom left area of the differential unit. Seems like there is a plate on the back of the unit I think. Does this have a gasket or something on it in behind the plate?

There is no info in Haynes about this. Anybody got any ideas why it is leaking and where from and how to stop it? Cheers.

 

[Ellsy Tanners]

Hi there,
The diff back plate is metal to metal fit with a sealing compound. no gasket is used and its unusual for this to leak.
You have three seals, One input (front) and two output flange seals, any of these can spring leaks with is quite obvious to see which one it is coming from.
If all three look ok, the diff is fitted with a breather valve, which is located in the top of the back plate which can give the impression of the back plate leaking.
If the leak is coming from the breather, make sure the oil level is ok, an over filled level can cause heavy breathing.

 

[jibcl500]

Show me a Mercedes Diff that isnt damp!!!!!! My C180 is the same, but two cans of mr muscle oven cleaner, get the car on ramps, spray all over the diff and then power wash off.
Check oil level in diff and increase if required, check the diff in a few days for leaks.

jib

 

[Stevie A]

Hi there,
The diff back plate is metal to metal fit with a sealing compound. no gasket is used and its unusual for this to leak.
You have three seals, One input (front) and two output flange seals, any of these can spring leaks with is quite obvious to see which one it is coming from.
If all three look ok, the diff is fitted with a breather valve, which is located in the top of the back plate which can give the impression of the back plate leaking.
If the leak is coming from the breather, make sure the oil level is ok, an over filled level can cause heavy breathing.

Cheers for info. I had a look at the Russian detail.ru site last night and I can understand the seals you mean. I'll check them and the breather. There seems to be some kind of rubber or something on the back plate from what I saw on the Russian site. If it is leaking from the back plate I will try tightening it up.