[93-5G20]

I bought a Bosch 3300 filter, because I needed one, everything else was closed, and supposedly the filter element gets good ratings.
After install, I quickly developed a leak. Thought it was the oil pan bolt copper washer....it was not.
Finally I did a change and found it was leaking out and down from the oil filter.
When I replaced with an OEM I found the OEM filter had a nice soft rubber gasket, and normal O-Ring.
The Bosch 3300 filter had a FLAT gasket, that was very hard rubber. Very hard, press your finger nail into it, and it barely dents.
The leak was caused when at preasure, it would squirt out. Spew out. The little oil catcher under the filter was entirely filled up.
This is not a single problem, its a design flaw IMO.

example of the flawed Bosch O-Ring, its flat, its hard, it likely will never fully seal against any defect or scratch on the oil mount.

another example

What a correct and normal O-Ring should look like. Notice it is round, squishy rubber that will seal.

The filter only leaked when driving, so if it sits a long time in one spot, the amount that falls won't increase with time, after the initial drips

 

[93-5G20]

this thread show exactly the way the leak looked from the outside http://www.g20.net/forum/showthread.php?135809-oil-leak

 

[Y2KG20]

I have used bosch 3300's for the last 12k miles. No leaks. with or without the sandwich plate that feeds the turbo. I use the same type on my mustang and jeep with no problems either.

 

[ENO]

yea same here i have used them & similar Oring style filters with no issue....

did you lube the rubber with oil before installing? also if its cold i heat the oring a bit with my heat gun to soften it, then rub a bit of oil around it....never had a problem

 

[reyesjnj]

i have never used OEM filter always fram or some thing else , and all the filters i have used have a flat rubber gasket. i have not seen any round other then your pic so to say it is a desing flaw is this to your opinion or a proven fact

 

[blankman3]

Never had a leakage issue with those type. I usually use wix brand filters though