We've been changing our oil and using Motrocraft 5w20. Has anyone out there found a synthetic offering with this FORD recommended multigrade. We would like to use the Mobil 1 5w30, but am worried about warrantee issues should some engine failure(s) come about. The engine has the dreaded erratic knock when cold and has had this anomaly since new.

Any help would be appreciated.

 

Hmmm...wild!

Hey, you can use 5w-30 w/out a warranty issue. Ford will not void it. It was mainly done for satisfying EPA and fuel consumption. Not all manufacturers think it is necessary.

BfB

 

I believe that amsoil and royal purple each have a 5w20 and they are both syns.

dan