Posted by Steve Kanavas on March 06, 1998 at 23:27:45:
In Reply to: synthetic oil posted by Pete Vernon on March 06, 1998 at 21:10:26:
Pete:
First confirm that the OEM gage is indeed accurate by testing pressure with a known accurate one.
Should all seem ok by this confirmation, you then have one or more of the following problems.
Badly worn oil pump
Relief valve damaged or mis adjusted
Large main/rod bearing clearance
Large cam bearing clearance
It's doubtful that synthetic oil will help the pressure issue. My 230 idles at 20psi and 45 psi at road speed in hot weather with approximately 180 degree oil temperature.. All the bearings in this engine are fairly loose... I use 20W50 oil.
the cheapest thing to try is to feed your truck a new oil pump. About $40 ish at NAPA.
Steve