Bought a 2010 Suburban in October with 160K miles, it now has 190K. I have been concerned about the oil pressure since day one after comparing the pressure to my 06 with almost 300K miles. Took it to my mechanic and told him I wanted a high volume/pressure oil pump put on so it would bump up the pressure. While he was at it, to replace the water pump, thermostat and anything else that had to be removed in the process. Waited a few days, got it back the idle pressure went from 35lbs to 20lbs. Told him it was worse than before so he mentioned it could need new rods and main bearings. Fine. Whatever. Replace that. Did that, still pressure at 20lbs at idle, 35-40lbs down the road. Also replaced the oil sending unit. Still low. So we tried another oil pump thinking the one we had was bad. Nope. Still low.

Is this normal? Do I need to be concerned? What's the fix for this or is that a normal pressure?

 

have you checked the pressure with a master gauge and confirmed the pressure reading accurate.

min specs for oil pressure at 10 psi per 1000rpm so you are well within min specs. if you want it up a bit for pom...if its not a dod motor...use thicker oil.

pressure is the result of restriction...what were the plasti-gauge readings with the new bearings?
your 06 is a different generation...compare apples to apples.

 

Sorry. I'm definitely not a car guy. Trying to learn, but still not there. As far as I know they've not hooked an analog gauge to the truck to test. They did, however, hook in their Snap On scanner and viewed the pressure there and it was consistent with what the gauge on the dash said. So 20lbs at hot idle.

If there's nothing to stress about then I'll learn to not stress. I just want to make sure I'm doing everything I can to protect my motor and make sure I get as much life as possible out of it.

 

I was browsing the forums and saw someone mention an AFM oil pressure relief valve COULD be an issue. My Suburban does have AFM, however I did buy a device that plugs into the OBD port to disable AFM. Should I replace this valve? Is it possible that is my problem?

 

Welcome to the forum.

My 2010 Tahoe had about 20 psi at hot idle and service said that was standard. I was always used to about 35-40 psi on SBCs.

 

the scan tool is reading pressure from the same pressure sensor that the vehicles gauge uses.

 

180K, slightly low oil pressure .... why not just use a higher-viscosity oil ???

Or - if oil pressure reads fine when not idling, maybe don't worry about it, very little load on engine at idle.

 

If you did all that work and nothing changed I would question if your mechanic actually did the work. If you know nothing about cars he knows that by you bring him the car for work. At a minimum you would notice it running a little different. If I ever have to take my car in I want to see what you are doing that way I know.

 

I do my own work... everything but transmissions. There is a difference, I don't see enough of it on the idle hot pressure as I would of expected is what I was saying.

The struggle is when I get the engine light to trigger "low engine oil pressure". I think I am fine at around 18/19 psi hot... just get the jitters is all and if I can easly bump it up a few, I would. The synthetic 40 weight will be my last attempt to mess with it and will be done by next week with a post of any noticeable change.

As far as my sensor and screen.... screen was spot-less and thrown out 40k ago. Sensor was switched back and forth with the original and new with no difference.

And for "GUYFROMTN"... I physically deleted my AFM... its all gone with a reflash on my computer to not address it. More response and power!!!! fuel Mileage stayed the same.. go figure

 

You are well within specs. I have a 2007 Suburban 5.3L with 325K miles on it. It sits at 20 PSI at idle which is about 605 RPM and has done so for as long as I can recall.