W170 SLK 230 auto oil leak

[Peter T]

My sons SLK has developed a substantial oil leak which he is convinced is from the auto box sump gasket.

The thing that worries me is that he did an engine oil change last weekend and a lot of the oil that's leaked out seems to be clean engine oil!

I've told him to give it a good clean underneath the engine/gearbox so we have a fighting chance of seeing the source of the leak. In the mean time, questions are -

1. What colour is the auto box oil. Probably a slightly silly question as it's probably completely black by now.

2. If is is the auto box sump gasket, is it much of a job to change?

Thanks in advance,

 

[Peter T]

Update

Further investigation reveals that there is an electrical connector on the front corner, driver side of the gear box, which seems to be the source of the leak.

Any clues as to what this might be and what needs to be done to cure the problem?

Thanks again,

 

[Dryce]

That will be the famous leaking electrical connector for the control unit.

Repairing Transmission Fluid Leak - Benzworld.org - Mercedes-Benz Discussion Forum

 

[paris2463]

Parts approx £18 from MB dealer very common prob very easy to do

 

[Peter T]

Thanks for the info. Parts on order.

It seems we were panicking unnecessarily!

 

[Peter T]

Job done, but not quite as easy as we were led to believe!!

Ignoring the usual problems of getting to the thing while lying on one's back with ATF dripping in one's eye, the dismantling was relatively trivial. Getting the new part in place, however was somewhat more taxing.

The new part slides in OK but not quite far enough to engage the screw, and all the pushing in the world by hand won't coax any it further into its' hole. There's also no way to tap it in as the exhaust pipe runs immediately in front of said hole.

In the end, and fearful of damaging the new part, we fashioned a hardwood plug to be a good fit in the lock ring and rest on the end of the body of the plastic part. We then used a small pry bar to lever between the wood block and the exhaust pipe. The provided enough extra movement to get the screw to engage. After that, it was plain sailing.

So, anyone else thinking of doing this job, arm yourself with a 1 1/2 inch cube of English oak with one face turned down to a suitable diameter before you start!!