2004 Vortec 5.3 Oil Pressure Sending Unit?

[mongocanfly]

mine doesn't hit 70 but it does run around 45 when driving..

[sprint_9]

I had one that would hit 60 pretty consistent when cold and run at 40-50.

[LBJ]

Got the reader, no new codes. So, hope the problems are gone for now.

[LBJ]

Lately, I have been seeing oil pressure readings of 80PSI and that's pegged! That happens when I am turning onto the highway and getting the heck out of the way of 18 wheelers. I now wonder if the gauge on the cluster is bad since I've already changed out the sending unit. Extreme oil pressure might be hard on the bearings, as in, eroding them. Is there any chance of that if the gauge is giving correct readings? Thanks. LBJ

[95 S_Trucker]

Use a scan tool and look to see if the oil pressure on the gauge matches the oil pressure the sender is seeing.

[LBJ]

Hi 95S Trucker, is the scan tool likely to be found with a pro mechanic? Don't think I have one, so, have to find one. Are scan tools expensive? Thanks, LBJ

I guess scan tool is same as code reader. Yes, I do have one of those! Sorry.

[truckdude239]

My tahoe hits 60-70psi cold and runns 45-50 warmed up down the road 70psi wont hurt the bearings

[LBJ]

Hi David, It does sound like hi pressure for oil, but, maybe it's OK. The Vortec's are different animals than the cast iron engines, so, as long as it's getting a positive readout, then that's good. I changed the sending unit, so, it's' not that. I've owned the truck since new so for the first 12 years I must have really never paid that much attention to the gauge. I also ran the code reader yesterday and no codes anywhere. Guess I'll live with it! ha. Thanks for the info on your truck's oil pressure. LBJ

[LBJ]

I was discussing this problem with a local mechanic. He said the Votec/LS engines have a problem with the oil pressure relief valve getting stuck. Usually they get stuck in the OPEN position but sometimes they get stuck in the CLOSED position. If CLOSED, then that might increase the oil pressure and display on the dash.

Now, I never asked him, OK, if that's the problem, what is the fix? Pull the engine? Or something less involved.

Any ideas?

[95 S_Trucker]

Originally Posted by LBJ

I was discussing this problem with a local mechanic. He said the Votec/LS engines have a problem with the oil pressure relief valve getting stuck. Usually they get stuck in the OPEN position but sometimes they get stuck in the CLOSED position. If CLOSED, then that might increase the oil pressure and display on the dash.

Now, I never asked him, OK, if that's the problem, what is the fix? Pull the engine? Or something less involved.

Any ideas?

Replace the oil pump if that’s the problem.

Did you have the local mechanic verify the gauge is showing what the sending unit sees? I’ve done dozens of sending units. I’ve never ran into a stuck pressure relief valve.

[LBJ]

95STrucker, No tests yet, just discussion. He said he'd have to pull out the sending unit, screw in a test gauge, and then see what it reads. Seems like a lot of work as I replaced the sending unit last year and it wasn't a fun job to get to.

I can imagine replacing the oil pump if it was LOW on oil pressure, but not HIGH. It would seem that with too much pressure there was something blocking a passage somewhere along the line. Of course, it could be just a bad oil pressure display in the instrument cluster.

[95 S_Trucker]

First step is verifying the gauge cluster is showing what the oil pressure sender sees. No need to unscrew the sender. It takes 3 minutes to do with a scan tool.

[LBJ]

I've got a scan tool/code reader but have no idea how to make it read the oil pressure. All it says is NO CODES.

[95 S_Trucker]

A scan tool will display data. A code reader will not.

[LBJ]

OK, give me a source for a scan tool! thanks, LBJ

[LBJ]

Would this be a suitable Scan Tool?

https://www.amazon.com/dp/B07B9VNCYK...detail_3?psc=1

Features

Autel TS601 Diagnostic Scan Tool for TPMS Check/Relearn/Sensor Programming, Full OBDII Functions, Printing Data, Lifetime Update

[truckdude239]

https://www.amazon.com/INNOVA-3140-O...y&sr=8-8-spell

Need one that reads live data this one says it does

[LBJ]

Thanks Dave, there's the key word I've been looking for: "LIVE DATA." LBJ