I have been using the purolator filters on my 2009 Subaru Impreza. Im not sure if the filters are defective or its my vehicle. There has been a little oil leaking from where the oil filter screws in. Its very minimal but my filter is located about the exhaust header, so when the oil drips it falls on the pipes and creates a nasty smell. I put the car on ramps today and tightened the filter some in hopes that it would resolve the leak and smell. I have been constantly checking the oil level and it hasnt gone down any. Are Purolator filters reputable? I have heard from several Subaru forums not to use them and to stick with the OEM filters. Does anyone know why the oil maybe leaking out? I switched to Mobil 1 OW30. This same issue occured when i was using Valvoline Synpower 5w30. Is this leake related to using synthetic oil?