During the last oil change on my dad's car, Festiva, we used a Purolator oil filter. I prelubed and tightened it so I know it had a gasket and was tight. He checked it later and it was tight but still had the oil leak. He lost about 2 qts in two weeks and had oil all over the engine bay. He replaced the purolator with a supertech and no more oil loss. Of course he didn't visually check it, so now I need to check it to be sure. I guess the only way to test it would be to try it on my car, I may fill it will oil and let it set a bit for giggles. I think I have the reciept but I've had this oil filter for months. If there is some defect should I contact purolator directly or take it back to Advanced Auto? Anyone with experience on this sort of issue?