Yeah...Thanks Bob because I must admit I liked the way the engine sounded and revved on the lighter weight Mobil 1
oil ! I did have some concerns though about the lighter weight providing the same protection. Sooo,I called Ford Racing Tech Line before logging back on and they confirmed what you said. They advised to watch my psi...if the motor is pushing out 40psi at idle on the lighter
oil and holding 60+ on higher revs go with the 10W-30. I'm changing back.