marko69

I have an oil leak where the trasmission and engine meet. It's more like a seep since I haven't seen any drops on the floor. Can't tell if it is motor oil or transmission fluid. Anyone have an idea where this could be coming from? I still need to clean it all down there to maybe get a clue where it's coming from, but I'm aking here first to see if it might be something common. Maybe the pilot bushing? A lot of the oil is along the insulation of this cable where I have the red arrow.

zenderfall

I have the exact same leak.

Whenever there's an oil leak between the junction of the engine and the transmission of a front engine/rear wheel drive car, the culprit is possibly the rear main seal on the engine side. Looking at how many miles you have, this is very possible.

I cleaned up the area and will inspect to see where more of the oil will seep through from, but I've already expected my case to be so.

The seal itself is not expensive but the labor for this kind of job can be high - the transmission has to be unbolted and dropped out for that seal to be replaced.

marko69

Man, I sure hope that's not the case. It's the main reason I sold the Catera to get this car. I'm pretty sure the rear main seal was leaking on it.

zenderfall

There's hope!

clean up the area and then check around the spark plug area and the top part of the valve covers. The valve covers on these engines are also known to leak, and since the heads are at an angle, it may be that oil is dripping down to that area from the valve covers.

I just did mine this past weekend. Hopefully that's where the leak was. It might be that in your case as well.

SwanLake

After cleaning the area, give it a day or two then wipe the leak with a white rag. If it's purple, you have a transmission leak.

I had an E320 that developed a transmission leak. It seems driving through a snowbank at the end of the driveway was not a good idea after all. Good news was that the replacement labor and part were'nt expensive

I have a 43 year old restored Triumph TR6. The line 6 engine is notorious for rear main seal leakage. The "6" community affectionately refers to the leak as British underbody rust-proofing.

mb techman

tell tale sign of rear main seal. but based on the color, there is a chance it is the pilot bushing for the transmission. highly unlikely the valve cover gaskets are the cause of oil around that area.

marko69

Well, I guess I'll be cleaning up the bottom this week, then digging into it this weekend. I'll let you all know what I find.

jonUF02

I've had a few cars with this type of leak. What would be the harm in letting it go if it's not even enough of a leak to drip down on the floor or loose enough oil to top off between changes?

zenderfall

I'm curious to know too, since I have the same leak. I cleaned it up and the valve covers this past weekend, and will see if it continues this coming weekend.

The harm in letting it go is that there will be an additional oil consumption of unknown amounts, not to mention the oil is getting into things you don't want it to go. If it's the transmission fluid that is leaking out, we now have no idea how much of that stuff is left in the transmission. And, it add to all that, the problem only gets worse, not better. The leak will get bigger over time.

eye of ra

Hi my first post and I’m resurrecting a year old post.


Recently got myself a CLK430, nice car but beginning to find a few things that will need sorting.


One of which is oil in exactly the same place, did anyone find out where it was coming from?

jonUF02

usually running down the back side from the valve cover gaskets. Easy fix with DIY thread posted somewhere.

prostock

Why are you worried about such a small leak? Check your oil as you normally do, and keep driving!

eye of ra

Thanks, Ill start by looking there this weekend.

Until I know where it’s coming from I wont fell happy leaving it in case its important and potentially costly if left. However as you say it could be perfectly fine to be left for more important things and if so I’ll just keep an eye on it, till/if it starts dripping and leaving marks on the drive.

prostock

Even IF it starts making it to the driveway, its a minor oil leak. Check your oil once a month, as you should be doing anyway, and top it off if necessary.

MUCH cheaper than repair, especially for something so minor.

eye of ra

Well had a look over the weekend and yes the R/H gasket is leaking. So not a major issue and there are more important thing to be getting on with for now.


Doesn’t look a difficult job however, thanks to all the helpful treads, so will do at some point in the not too distant future.


Thanks for all the advice.

Bubby

Well believe it that's the case. It's the rear main seal I have the same problem on my car 99 CLK 320 and most of all my cars with over 100,000 miles

marko69

Wow, that was 8 years ago. My wife still has the car. I haven't looked into the leak since then, no drips on the driveway so I just let it go.
My SL500 is doing the same thing but worse. I was getting drips in the garage daily and after our cross country trips there was a lot of oil covering the underside. I'm pretty sure it's the rear main seal. I will be keeping this car forever so I'm just waiting for the right time to get er fixed since it's gunna cost a lot I'm sure. In the meantime I used a sealer called Full Throttle FT40204, and it has worked beautifully. I still get a drip once in a while but not like before. I really hate using any kind of miracle sealer or oil additives but I wanted to delay this $2k repair for as long as possible. It also worked great on my leaking hydraulic strut's. It's been over a year and many miles now with no problems.