Which oil to use

[KShortell]

To be honest, I've had good luck with Valvoline for many years. I used Pennzoil a lot in the past as well. The only oil I even had trouble with was Texaco Havoline about 20 years ago. It just wouldn't hold as much oil pressure as other oils- thinning out, perhaps?

I run straight 30-weight Valvoline in my boat with no trouble. A boat engine is like a car or truck floored in 2nd gear going uphill ALL THE TIME. The internals on my GM 4-banger in the Bayliner are clean and look really good. The fact that I had to pull the head a few years ago had nothing to do with oil, but with me running the manifold and elbow too long. Doh! Anyway, the cyliners, etc. weren't all scored up, compression is good, etc. I'm nearing 500 hrs. on this motor.