Agreed, correct oil weight is just as important as quality of oil, I run synthetic blend 50/50 from Castrol. I run it in my Titan, Pathfinder, quads, and tractor. Never have had any oil related problems. Heavy v8. Lite v6. . High torque in line 4 diesel, or high revaluation single piston. Can't hurt it, but can help with heat and lubrication. IMHO