I am getting ready to order a new mustang. The only thing that really bothers me is that Ford recommends 5w-20 oil. I was just wonder after the intial break in of the engine would it be ok to use syn mobil 1 5w-30. I realize the new fords are biuld will tighter tolerances but the 5w-20 really makes me nervous. It seems to me that Ford doesn't care about their engines lasting, or minimizing wear, just thinking of the gas mileage. (CARP thing I think). Or what is a recommended viscosity besides 5w-20, that works well in the new 4.6?