Oil Leak... from HELL (Story thus far)

[Fifty150hs]

Originally Posted by cn90

I have a 1998 528i M52 with 170K and 2006 X5 M54 with 125K.

Thanks for the Viton info.
- BMW OEM OFH Gasket = $6.
- ECS Tuning Viton Gasket = $20.

The factory seal leaked at 10y/110K miles. I think if the BMW OEM seal gives me 10y/110K service, it is fine with me. I don't keep cars beyond 200K miles.

Does anyone know how long the Viton seal lasts?

Don't know exactly how long, but from what I've read significantly longer than the BMW seal.

"Viton o-rings are an alternative to Buna-N seals in BMW's automobile engine variable timing units, known as VANOS. In the VANOS, the Buna-N o-rings deteriorate. The Viton fluorocarbon o-rings have similar functional characteristics to Buna-N, but with much higher temperature and chemical resistance characteristics."

https://en.wikipedia.org/wiki/Viton

[mig25]

I just fixed an oil leak from hell on my X5. My oil leak cam from the Camshaft position sensor O ring .
It sits right up front the engine in the VANOS you don't even have to remove anything to replace it. I bought the O ring OEM from ebay $5
Here is a picture of mine 3.0i Sensor.