Low Oil Pressure

[TeeJay3800]

Tonight I sat in a drive thru for 1/2 hour and the motor got pretty hot (fans kicked on at 227). After that I noticed my oil pressure seemed lower than usual (maybe it was lower before I didn't notice). It only showed 3 "bars" on my digital gauge at idle, and didn't rise up as much as normal when I stepped on it. I recently did an oil change with the PF52 filter, semi-synthetic 5w30 oil, and a dose of Restore.

What could be causing the lower pressure reading? The fact that the motor got hot for a time? Could using restore cause a drop in pressure? Maybe tomorrow the pressure will be back up to normal....hopefully.

What do you guys think?

[geoffinbc]

Well heat and thin 5w30 oil will cause pressure to drop. But nothing to be concerned about.

[sharkey]

if you have mild winters, next oil change you do use 10w30, and if your over the 75000 mile mark, use high mialage oil. it does work, i find i get an averange of 10lbs more oil pressure then if i use regular 10w30.

[TheProfessor]

yeah 10W30 is good to use in michigan
5W30 would be better for like norther canada

[TeeJay3800]

Michigan winters are still cold as hell. I cringe every time I crank it on a 10º morning (which is not uncommon). 10W30 is only good down to 0ºF and we get lower than that here. Besides, the manual and oil cap recommend 5W30.

[geoffinbc]

Just keep using the 5w30. 90% of new cars are suposed to use it. If you are still worried then get a mechanical guage and check. But I am sure you are still just fine.

[TeeJay3800]

Pressure was low again today, even when at normal temp. Kinda scary that it sits just above the red zone at idle, but I'm not going to worry about it. Thanks for the info guys.

[geoffinbc]

Like I say you really need a mechanical guage to know.

[korbendallas68]

Check the oil pressure sensor. It's not that expensive if I remember.

[TheProfessor]

dude if your gauge is just above the psi mark and your engine still runs id say that the gauge or the sensor is fucked somehow for sure

[TrailMug]

I believe 11PSI at 1100RPM is all that the GM manual says is required, but I'm not sure I'd be comfortable with oil pressure that low. Double-check with a mechanical gauge (remove the gauge sender by the oil filter and screw in the mechanical gauge). If it's low, time to check for worn oil pump or bearing/journal clearance. Try the next oil change without the restore to check that stuff out.. I think those additives usually raise viscosity as opposed to lower it, but it's worth investigating.