Ashley denn

Just bought 07 suburban. When you start it up in the morning oil pressure is is around 10-15 after it warms up goes to 22 at idle when rpm’s go up it goes to about 38-39. This just seems low to me definitely at start up. Motor has no noise runs smooth sounds good. Also I think there’s I. Issue with the coolant gage and battery gage both drop down extremely low when truck is off and when running only go up a little past a quarter of the way

kevinkpk

That is fine, general rule 10 psig per 1000 rpm.

73shark

My 2007 and 2010 Tahoes both showed low oil pressure at idle but came up to about 35 psi to 40 psi at normal RPM. When I pointed this out to the service manager, he informed me that this was normal. As far as your coolant and voltmeter goes, the coolant should read about 190° to 200° which would be about straight up and the voltmeter should read about 12.7 to 13.5 volts . Again the voltmeter would normally be about straight up with the engine running.

denn

I know for a fact it is not normal for my truck to only have 10 psi oil when I first start it in the morning and i have never seen it hit 40 when driving but it comes close. I have had 3 other 5.3 trucks and all of them had much better oil pressure.usually at start up oil pressure should be around 50 and come back down as the engine gets gets warmed up Also. Battery stays at about a little over a quarter of the was sometimes lower and same with coolant gage. Suburban seems to run good no check engine light sounds good nice and quite

bearbait

Could possibly need an oil pressure sending switch. Also there is a screen filter below switch that tends to clog with age. Shops claim the intake manifold needs to be removed but I changed a 2008 Tahoe without doing that. Changed unit and cleaned screen and everything went back to normal.

denn

what was yours doing before you changed it

bearbait

Was reading low oil pressure.

repairman54

Replace the sender when pulling out the screen under it. Use only a Genuine GM sensor for no issues.

Cusser

Even the kid next door was able to replace his oil sending unit without taking all that stuff apart, or taking off the hood.
My 2005 was sometimes getting "low oil pressure" reading on the screen, but oil pressure gauge always showed OK, and our mechanic said to just leave it and not change the sender.

bearbait

Shop wanted $400 to change it. Took 45 min. and about $30 for sender. Need a large size socket ( can't remember size) and extension. Tight to access but can be done. Good luck