my car runs at around 20-25 pounds of oil pressure no matter how fast or how high the rpms. shouldn't that be a little higher? and if so what could be the problem? thanks

T-Pat

 

how many miles ya got?

 

the car has about 125K on it

 

Have you thought about changing the oil pump?

 

yea i have but i was wondering if it would be something else before i dive into something like that

 

what kind of oil filter do you use, fram by any chance?

 

Try a K&N filter and full synthetic 5w 30 and see if that helps.

 

i generally use delco for oil filter and castrol 10-40 for oil. not a good choice?

 

If you're using 10W40 and getting pressures that low, then something is wrong. It's probably the oil pump needing replacement. You don't have any odd sounds like a knock or something in the motor, do you? If so, that might explain it.

I hope, for your sake, that it's just the oil pump. That's probably the cause.

 

Castrol is good oil. and a delco filter should be fine. I would say there is probably something wrong with the gauge or the pump. hook up a mechanical gauge and take a reading.

 

theres no knocking or anything so i figured it was the oil sending unit or something along those lines...

 

You could hook up an oil pressure gauge directly to the motor, but that's kind of a pain in the ***. The oil pump is a relatively easy swap, should take about 3-4 hours.

 

When you change the oil pump, there will be 2 different size O-rings for the pickup tube. Always use the thicker of the two. I used the thinner one at first and had crappy oil pressure, so I had to tear the whole thing back apart and stick the thicker one in. I have 150K on my engine and it pulls 35PSI at 900 RPM idle and up to 65-75PSI at higher RPMs. Your engine should be fine once you replace the pump. If not, you have bearing issues.

 

listen to the man!! and dont drop that oil pickup tube bolt

 

thanks for the info!

 

theres a good chance that the oil pump could increase the pressure, but with 125k, possibly a hard 125k miles, theres probably some wear resulting in increased bearing clearances and causing low pressure, hopefully for you its just the pump, good luck!

 

More than likely your Oil Pump is having few issues, but also bearing clearances over time, pick up, etc. could be problems.

Hook up a mechanical gauge first to see if it is not the faulty GM gauges.

If still low, pick up an LS6 pump or high volume unit, and replace. Should be 3 hours or so. (While you are at it, you should add in a cam and what not too. )

 

ok, now sometimes my car shows between 35-40psi but it will eventually drop down to 20-ish. is that moreso the gauge acting up or can that still be the oil pump...

 

I say the first step should be to check pressure manually. Even if it is a pain in the *** its not going to surpass the cost of a new oil pump and the time required to change it out.

 

yeah, i would verify oil presure is reading correctly with the manual guage first