Before choosing a synthetic oil, check out:
www.msprotege.com/forum/showthread.php?t=32904&page=2&pp=15&highlight=mobil+horseshit
TheMAN points out that true synthetic oils use ester based stocks with no organic content. Examples of these oils are Red Line, Torco and Spectro. On the other hand, Mobil 1, Amsoil and Castrol use PAO base stocks that are derived from organic materials (mineral oil) in the production process. The Feds allow a PAO based oil to be labelled synthetic if the mineral oil structure is modified, but these are not true synthetic oils. This is why I use Red Line oil in my own engine.
02 DX Millenium Red