[fspheil]

I have looked at a ton of pictures and read countless threads about oil leaks on N54s. But I wanted to see if I could get some feed back on my own, won't go away oil leak, specifically. I changed the valve cover gasket about 25,000 miles ago and the car has 114,000 on it now. Since that time I have replaced the turbo's with all new lines, oil pan gasket, oil filter housing gasket as well as the vanos gaskets. most of it was done in the last 4,000 miles. I had some bad leaks so it took a bit for the residual oil to dry up but it still leaks.

Rear Main Seal?
I don't think so as I took off the rubber cover at the bottom of the transmission and it seemed dry

Oil Pan
Just did this and it is clean

Oil Filter
Same as above

Valve cover
Seems clean when I take a mirror around it and this is looking from the top and the bottom but with that being said.

I have attached a picture which shows oil on the lower motor mount bolt and on the seem between the motor and transmission. And what makes me think it's the VC is oil on the rear turbo intake on top. I see no oil on the turbo around the oil in or out. I also see oil on the left side motor mount but I think this might still be residual oil.

I put the car on some ramps and ran it for 15 minutes or so after cleaning all oil spots. It didn't leak while running but after turning it off I did see oil between the mote and the transmission but it stated up around the motor mount area.

Any thoughts?

[blown07]

Check that your flapper valve connection or PCV hose to the valve cover isn't leaking. It was on mine and caused oil to leak down the back like that.

[mweisdorfer]

Originally Posted by fspheil

I have looked at a ton of pictures and read countless threads about oil leaks on N54s. But I wanted to see if I could get some feed back on my own, won't go away oil leak, specifically. I changed the valve cover gasket about 25,000 miles ago and the car has 114,000 on it now. Since that time I have replaced the turbo's with all new lines, oil pan gasket, oil filter housing gasket as well as the vanos gaskets. most of it was done in the last 4,000 miles. I had some bad leaks so it took a bit for the residual oil to dry up but it still leaks.

Rear Main Seal?
I don't think so as I took off the rubber cover at the bottom of the transmission and it seemed dry

Oil Pan
Just did this and it is clean

Oil Filter
Same as above

Valve cover
Seems clean when I take a mirror around it and this is looking from the top and the bottom but with that being said.

I have attached a picture which shows oil on the lower motor mount bolt and on the seem between the motor and transmission. And what makes me think it's the VC is oil on the rear turbo intake on top. I see no oil on the turbo around the oil in or out. I also see oil on the left side motor mount but I think this might still be residual oil.

I put the car on some ramps and ran it for 15 minutes or so after cleaning all oil spots. It didn't leak while running but after turning it off I did see oil between the mote and the transmission but it stated up around the motor mount area.

Any thoughts?

If you did the valve cover gasket correctly, it should last 50 to 75k assuming you did not use any Ultra Black gasket maker as a back up. If you did use Ultra Black by putting a bead in the seams of the valve cover where the gasket goes first, pressing the gasket into the seams, and then applying another bead of Ultra Black on top of the gasket, it should last well past 90,000 miles.

I like the above posters idea of checking the PCV valve hose. Those should be replaced as well as the PCV valve every 50,000 miles. If not, you will get oil leaking down he backside of the engine.

RMS - you are starting to be on borrowed time with that gasket unfortunately. Don't be surprised if the RMS goes before 125,000 miles on your car. There is not a step by step DIY on the RMS. There is lots of discussion and some pics here on this forum. If you have DIY'd the items in your original post, it should not be an major concern for someone like yourself.

[Cruiser124]

I'd bet rear main seal. Went through the same ordeal. It won't necessarily leak out of the plug at the bottom of trans because of gravity and the way the engine slopes..

[fspheil]

Thanks Blown07 for the idea's but I guess I forgot to say that I changes the tube with the VC and I did the PVC valve upgrade a few months back. And I hope I did the VC correctly Mweisdorfer but it is an assumption So Cruiser124 it must be the RMS and if as Mweisdorfer suggesting it is a goner at 125K then that must be it. Since I work on jack stands dropping the transmission doesn't sound like fun so it's time to get someone else to fix it. Any idea on cost?

[Snypa]

The oil filter housing gasket has some weird ways of leaking, but if u check underneath it and looks clean, then you should be good. The VC was a pain in the ass for me, if it has a hairline crack, it will leak as well. Last but not least and never to leak is the bedding seal.