Well I'm currently using Mobile1 regular synthetic oil 5w20 in my mustang gt and I'm wondering if I should change to Amsoil, wondering whats the weight I should use for the Amsoil and how do I know which filter fits on my car, or the part#
Which filter or filters is the best for synthetic oil ? And which other oil brand would you recommend if any. Thanks guys, seems like theres lots of oil knowledge in this forum and the reason why I joined. 

