Last week I changed my oil and filter for the second time since I've owned my 2004, which I purchased earlier this past spring. Each time I have had difficuilty with the large O ring that is above the threds on the plastic recepticle that holds filter. It seems that again the O ring failed, loosing its shape and allowing oil to seep out. Each time I've tightened the cap as tight as I dare with an oil filter wrench, ensuring the the O ring is still round on all sides. Then after the engine is warm I bring the RPMS up and increase the oil pressure to ensure that its not leaking. Each time I've changed the oil I have had problems with the large upper O ring which becomes compressed and gets out of round. I have not had a probelm with the new filter & O ring untill today. Prior the O ring was fine and not leaking. Today on a trip I had my foot into the throttle a few times and happened to notice what appeared to be exhaust smoke at approximately 90ish MPH when passing?? Got home poped open the hood and saw a mess!!!!!! O ring is flat on one side and leaking??? Is this normal??Is there a secret to installing the Oring?? Tightening specs??