last thursday while driving over 55mph on the highway i noticed a shuttering effect on my car almost as if driving into a strong headwind, but after i slowed down it went away, the same thing occured on friday when i was again on the highway, but with local driving there was no shuttering, coming home on friday i noticed a small puddle of oil in the driveway, so i popped the hood and found a lot of oil splashed around by the oil filter, i also saw oil dripping from the filter. I had recently done an oil change about two weeks earlier, and must confess i used a purolater filter, (but i had not had any problems with them on my old vw before). I was wondering how the hell this could have happened after quickly shutting off the engine. There were no oil warning lights or anything that came on. Anyway I was forced to do an oil change, so i picked up an oem mann filter. when i drained the oil, there was only about a quart and a half left. Crap! how come the lights didnt go off. I am still wondering what the hell happend and am praying there was no invisible internal damage. We have had below zero weather and i was wondering if the purolater filter might not have been able to stand up to the temps, and that why it was leaking. Anyway my car seems fine but my mind is still not secure. Does anyone have an analysis or recomendations? If you have any questions please ask. also after analyzing the purolater filter and the oem mann filter i must say i will always go with an oem filter because its much heavier and seems much stronger.