The owners manual for my 2001 5.4 4x4 F-150 says Ford recommends using 5w20 oil. This is something new, in previous years Ford had recommended 5w30. Would this have anything to do with the "piston slap" problem some of these engines have had? I've noticed this engine w/aprox. 400 mi. on it is a little noisier at idle than my '99 was.

 

5W20? On my 2000 5.4, Ford recommends 5W30. The lighter weight oil really has nothing to do with piston slap or to cure any (alleged) deficiencies, just helps to meet the EPA mileage targets. (Now, what's this about piston slap? The Ford modular engines haven't had any clearance defects that I'd ever heard of... is this something new?)

 

I've seen several messages on the boards about "piston slap" in the 5.4 engines on start-up. That was the reason for my question. I had a '99 with 5.4, no PS--however it was a little quieter at idle than my 2001. I have searched for 5w20 oil, not to be found in my area. Will likely have to use 5w30--as was recommended for '99. Does anyone know who makes Motorcraft oil for Ford?