My 98k mile 1997 SS runs about 40-45 @ idle ... 50-60 @ cruise rpm & up to 65 or so when running through the rpm range. It's a stock short block with H/C/I for the last year or so.

My 130k mile 1995 Formula runs about 20 @ idle ..... 40 @ cruise rpm....and get's near 60 psi as it approaches 6,000 rpm. It's bolt on only so I don't turn it higher than that.

I find it kinda funny that the SS has better oil pressure than the Formula when it has been beaten on far worse.

Have you put a mechanical gauge on it yet? You can pick one up for less than $20 I think.

 

Would a cold start show lower? Can't say for sure that my relief valve is stuck... But from what I remember when tampering one day is 60psi @idle and any gas makes it jump to mid 70's. After it comes back to idle, it idles @70psi. And will max out the gauge with any gas given. Shut off motor, restart, idles at 60psi. No wait time. This sound like its the relief valve? How easy is it to damage? I recently replaced my oil pan gasket...


I would be happy with either of those numbers. I have something that is off. Thanks for the input!

 

Your pressure will be higher when it's cold because the oil is thicker until it gets to operating temperature.

I bet when you check the pressure with a mechanical gauge you will find yours is lower than your instrument cluster is reading. If so, then you know it's the sending unit or the wire to it.

 

I did check it with a mechanical gauge... See my second to last post on page 1. It confirmed my dash reading was accurate.

I was asking about a cold start showing lower bc if my relief valve is stuck, I was assuming it would gradually lose pressure after sitting for a while, then cold start would show lower only until the oil pressure was built back up, which wouldn't take long...

 

Okay changed oil yesterday. 5w-30. Initial start up read 60, gas read 75 and it stayed there after that. So I am99.9% it's the oil pressure relief valve. My question is do these things have a reputation for returning to working order, or how much of a PITA are they to install?

 

You have to drop the oil pan....

 

sp basically take out motor mount bolts, jack the motor as far as possible, drop the pan, bolt off the old relief valve and bolt on the new? can u just buy the relief valve? i did a quick search on google, no luck, but a new melling oil pump with the relief valve incleded is like $50, which i am not complaining in the least, so should i just go ahead and get a whole new assembly? or is the GM pump better quality, and should be kept?

 

Bump, want to get this fixed, like to know the best approach. Guru's?

 

mine runs high too, always has. 178k on it.

 

i need to fix mine. i am sure the relief valve is stuck. all that pressure is not good for the system. i reved and hit 90 psi on a 3k rev. imagine a downshift and floor to 6k.... the oil filter seal blows at about 100psi give or take. i bet i could see 130ish...

 

I'm contemplating leaving the relief valve closed, and just buying the biggest best oil filter that I can for it. I've dropped the pan once, and I know it's a bitch. Pump pushes 9 gpm, k&N oil filters are rated at 12-16, so as long as I start out easy on it until it warms up, I should be good. Don't really want to, but nobody seems to want to share the knowledge of how one goes about replacing the relief mechanism, or what assembly I need to purchase to have the parts to solve my problem...

 

if you're going though all the trouble to remove the pan. you should just change the whole pump why even take that chance. I would also spend the extra twenty bucks and buy the oil pump shaft with the steel retainer and also install an pickup tube retainer. ive had the pickup tube fall out on me twice in two years the first time I tacked it on the second time I welded it all the way around and used the retainer clamp its not going anywhere now...lol