First of all I'm new here...been reading for the past couple months and have learned a lot from you guys. I bought a 2005 Mustang Gt in August and did my frst oil change using RP in November. After reading several posts on here about PP I decided to make the change. I just PP 5w-20 in and drove around town running a few errands. It might just be my mind but I swear my engine is running more quietly. At the rate I'm going now I'll be lucky to put six thousand miles on her a year. I think I'll be sticking with this oil if things continue this way. Plus I can get it at Wal Mart along with the Motorcraft filter.