Originally Posted by moosestang
And 5w20 is something Ford uses to meet CAFE standards. If you really beat on your car, I'd run something with a little stronger film strength.
Yeah, 5w20 is not necessary. I've used 10w30 with no ill effects whatsoever. Considering I drive in hotter climates (Texas), 5w20 can at times be too light even in just daily driving. Even in just a mild 110degree F Texas summer day, that outside heat can contribute to your engine operating temps, especially in humidity where the ambient air is already "saturated" with heat and your radiator is struggling to discard the heat into that sauna-like wet air.