Tuesday, March 16th, 2010 AT 7:56 PM
My oil pressure sits at about 39 PSI idling, and would always stay in between 39-42 PSI. I recently changed the oil, and used 5-20 instead of 5-30 (wasn't thinking). I also went from a Fram PH9837 Extra Guard Pro to a Fram PH9837 Extra Guard. Now when I my RPM rise to about 3,700- 4,000 RPMs (passing gear) my oil pressure will rise to nearly 80 PSI. Any ideas? Possibly the lighter weight oil or a bad oil filter?





