Originally Posted By: Hitzy
My Jeep 2.4l world engine calls for 5w20 in the manual. Same Jeep exported to Europe calls for 5w30. Same Jeep sold in Australia calls for 10w40.
5w20 is fine oil for most cars, but it is strictly a CAFE requirement, no such thing as "the tolerances are too tight for 5w30" or "the engine was designed for 5w20", thats all a load of [censored].
Use 5w20 or 5w30 in your ford/mazda, whatever you want will work just fine.
Clearances . The clearances are too tight. tolerances are the allowed variation allowed in the clearances. for example .0025 clearance + or - .0003, I made up the numbers.