Okay so my father changed the oil in my moms 2001 Grand Prix GT (3.8L v6) to Mobil 1 10w30 and an AC Delco UPF52 filter. He drove it and everything was fine. The next day, my mom comes home from the store and says her engine is making a lot of noise, her low oil light is on, and it smells like something is burning. This cant be good. My mom knows nothing about cars (she doesnt know how to fill the car up with gas... my dad and I always go with her and fill it up when it needs it) so the car could be pouring smoke and she would still keep driving... so dont ask why she didnt pull over when she smelled burning, heard noise, and saw the low oil light. I got outside only to see the side of the car completely covered in oil and smell nothing but oil. I opened the hood, looked at the filter, only to see it was quite aways from being correctly seated. I checked the oil level, nothing showed up on the dipstick... crap Either my father didnt tighten the filter properly (though he says he did) or something happened to the filter. Whatever happened, the threads on the filter are shot. They are pretty much non existant. We retraced my moms path home and at a location about 10 minutes from our home there is a very large oil stain on the pavement where the filter blew itself down and oil started pouring out. I ran to Wal-Mart and grabbed a 5 quart jug of 10w30 M1 (for $18... glad its on sale ) and a supertech filter. Put the filter on, put the oil in and started it hoping for the best. Well, the motor sounds like it did when it was new and runs smooth. Everything appears to be normal, but what internal damage could be done? Is there any additive that I should try? Or just keep running Mobil 1? Either way... I have a feeling if Mobil 1 was not in that car and the usual Valvoline 10w30 dino was in there, the motor would not be running as nice as it is now. Thanks!