i was wondering what you thought about running this in a 2004 mach 1 mustang. the car has 120,000 miles and has began making a ticking/tapping noise. it only makes the noise when it is hot and at idle.cold engine= no noise and reving the engine past idle, hot or cold = no noise. it makes me think it is an oil pressure deal since the oil thins when it gets hot. 5w20 is noisy, 10w30 is less noisy so i was thinking 5w40 would be great. (plus there are some ford guys that swear by a diesel spec oil in these dohc engines. let me know what you think.)