oil pressure

I just recently purchased a 2002 k2500 Avalanche w/ Vortec 8100 (app. 30k miles) from my local dealer. During the pre-purchase test drive I noticed that the oil pressure gauge registers 65 psi at idle and 75-80 psi with the rpm's at or above 2500. After the engine is up to temperature the oil pressure values are about 5 psi less. The dealer's service department informs me that this is normal for this engine. Is this indeed the case and, if so, what use is an oil pressure gauge that reads at/near maximum whenever the engine is running?

This is not normal. I have a 2002 k2500 and it has 36k on it and it hold almost 65-70psi above 2500 not or cold and 20-25psi hot idling. If the one you drove has 5psi either it have a bad guage or a bad sending unit.

I just recently purchased a 2002 k2500 Avalanche w/ Vortec 8100 (app. 30k miles) from my local dealer. During the pre-purchase test drive I noticed that the oil pressure gauge registers 65 psi at idle and 75-80 psi with the rpm's at or above 2500. After the engine is up to temperature the oil pressure values are about 5 psi less. The dealer's service department informs me that this is normal for this engine. Is this indeed the case and, if so, what use is an oil pressure gauge that reads at/near maximum whenever the engine is running?

yes it is normal
cold oil = higher flow resistance therefore more oil pressure
hot oil= less flow resistance therefore less oil pressure
you will see that with any engine, gas, diesel or turbine

Oil Pressure - Hot

Minimum
34 kPa @ 1,000 RPM
5 psi @ 1,000 RPM

Minimum
69 kPa @ 2,000 RPM
10 psi @ 2,000 RPM

"what use is an oil pressure gauge that reads at/near maximum whenever the engine is running?"

It tells you the oil pressure. If it drops, you'll know something is wrong.

oil pressure should be high when the engine is cold, the higher the better, you can never have enuf oil pressure, lubrication is your engines life blood, gm does allow for a real low pressure around 5 psi warm around idle, me pesonally if it goes below 10 i change the oil and the pump. and as far J-RI goes :screwy: he is nuts, says he is a mechanic but all his posts just are dumb. the kid hasnt got a clue about cars or trucks. he is a kid, maybe he will learn but so far all the posts i've read of his are just missinfo. :loser:

"what use is an oil pressure gauge that reads at/near maximum whenever the engine is running?"

It tells you the oil pressure. If it drops, you'll know something is wrong.

Yah right, "you can never have too much oil pressure" THAT IS UNTIL YOU BLOW OUT THE OIL SEALS AND BALLOON THE OIL FILTER TIL IT POPS.

These are electric gauges and not to reliable at best. I'd say it's fine as is, not too many engine problems that would cause high oil pressure, low pressure would be something to worry about.

Before I say this, I highly respect all workers, reguardless of what they do, if they act as professionals.

84fiero123 was an assembly line worker, and a welder. Any knowledge of cars was from putting them together, and some repair work. I thought we had discussed this through PMs, but apparently he is still bashing me. The following is from his post in the "Silverado" forum in the thread "What age are you guys mostly, and what kind of work do you do?", and I'm sorry that I have to drag outgoing personal information into this.

"ok i guess i get the old man badge. 49, 50 next week. worked for GM at the assembly plant in framingham, mass from 73 until 89 when it closed, as everything from a line grunt to repair, went to saturn in 91 then moved back here in 95 to maine, (daughter alergic to the entire state) now work construction as a welder, carpenter, and anything else that pays good, no one touches my cars, trucks unless its trany work and even then i take trany out and replace, sorry guys i dont own a CK just 2 burbans, but mechanicly mostly they are the same had a stroke last dec. and the doc said to take a year off. thats why i'm here so often, just trying to help and keep myself buisy."

I'm getting sick of these under the table jabs at me, it seems like if I reply, he has something against my answer. I'm sure he knows a lot, but there's no reason for slander. I have probably posted a few posts that were not 100% accurate, but misinformation (yes, 1 'S', and the rest spelled out) goes a bit too far.

I challenge you, 84fiero123, to find any of my posts that are dumb, and post them. After all, if all my posts are dumb, and I have over 700, they should be easy to find. Lets see what everyone else thinks about the correctness of my posts. Otherwise, I expect that all posts such as this will cease immediately. If you have a problem with this, please PM me. As for posting my "dumb" posts, I give you permission to use ANY of my posts, from ANY time, in ANY forum.

About my post in this thread, quoted by rrousou, I meant it gives you a good indication of oil pressure, and a big change overnight is cause to believe there is a problem. Sometimes my brain gets ahead of my hands :)