Oil Pressure Drop-This OK?!

[eldrijt]

While driving in bumper to bumper traffic (rare for me), my oil pressure dropped from it's usual 40+ psi to about 30 psi. Pretty dramatic drop I think. Temp went up to 210 as well. After I got free of the traffic and resumed highway speed, the temp dropped fast but oil pressure didn't return to normal for several minutes. Now I know temp is water temp so maybe oil just took a while to cool and return to thicker viscosity. For those of you who drive in traffic a lot is this normal or is my oil pump going out? Oh, and it was about 82 degrees outside. Not that hot.

Thanks,

Jim

[Hi-Po]

You need to post what RPM you were seeing when your oil pressure seemed to be lower. A GENERAL rule of thumb that I dont really live by, is 10 PSI per 1000 RPM.

I still think thats an understatement, buts its something that gets tossed around alot. Check to see what RPM and what pressure you have.

[9T8W66]

Minumum Oil Pressure and RPM
6 psi @ 1000
18 psi @ 2000
24 psi @ 4000

[Hi-Po]

Minumum Oil Pressure and RPM
6 psi @ 1000
18 psi @ 2000
24 psi @ 4000

If I had 6 PSI at 1000 RPM... The car would not be going down the road. Those are the absolute minimal oil pressures. Where did you get those numbers?

[pajeff02]

If I had 6 PSI at 1000 RPM... The car would not be going down the road. Those are the absolute minimal oil pressures. Where did you get those numbers?

I'd be shutting the car down and plumbing in a master pressure gauge in a hurry to see what was going on.

To the OP: The temp gauge isn't all that accurate. I have had our car around 225 degrees with the dash gauge reading almost 25 degrees lower. What weight oil and how long since changed?

Ooops. Just looked again - my understanding is the '98 gauges may actually read correctly.

[Hi-Po]

Ooops. Just looked again - my understanding is the '98 gauges may actually read correctly.

Your understanding is correct

[BMJ99Z28]

While driving in bumper to bumper traffic (rare for me), my oil pressure dropped from it's usual 40+ psi to about 30 psi. Pretty dramatic drop I think. Temp went up to 210 as well. After I got free of the traffic and resumed highway speed, the temp dropped fast but oil pressure didn't return to normal for several minutes. Now I know temp is water temp so maybe oil just took a while to cool and return to thicker viscosity. For those of you who drive in traffic a lot is this normal or is my oil pump going out? Oh, and it was about 82 degrees outside. Not that hot.

Thanks,

Jim

I live in Decatur Al, been hot here huh . 30 psi is about normal for me idling at a red light ( after warmed up, factory guages) .I,ve had three ls1 f bodies all 99's and 210 water temp in stop in go is and was not out of the ordinary on all of them.Its just finally got F'n hot down here. Who did you buy your car from is it a cammed auto ? I know a guy that had one for sale he called it Kermit.

[JoshieDoom]

If I had 6 PSI at 1000 RPM... The car would not be going down the road. Those are the absolute minimal oil pressures. Where did you get those numbers?

Those are gm specs and they will not do anything about low OP unless it gets below 6-8 psi at hot idle depending on the car, father has been saying that for years....

Pressure doesnt always equal flow as well.


If I get below 30 psi im getting nervous. I would like to install a little bright ass light into my dash somewhere hidden so if my oil pressure drops below 10 psi it blinds me.

[eldrijt]

This is a 6 speed stock LS1 with recently (1500 miles) changed Mobil 1 synthetic. To my fellow Alabamian I bet Kermit was owned by my mechanic, Lane Culver. He had a Bright Green Metallic car like mine and called it Kermit.

Sounds like I'm OK with 30 psi. Just looked scary dropping that far.

Thanks to everybody who replied.

Jim

[DaddySS]

My C6 had an oil temp reading in the DIC and it took much longer for the oil to cool down than it did the coolant. 30 psi on a hot engine with hot oil is plenty, no need to worry.