Hello! I am new to the forum here I have been a viewer for years and have found a lot of good info on here in the past. I have done some searching on this many times and find a lot of mixed answers. So Im looking to buy a c6 here soon. I am very familiar with the ls motors I just sold my 2000 silverado with a built ls2 and have tinkered with ls1 and 5.3s many times. Well I went to buy a car last weekend and when I got there and the car got to about 210 degrees the oil pressure was at about 22lbs and it was about 26 degrees outside that evening. There were some other red flags that the car had really been drove hard and that oil pressure really scared me so I took the safe bet and walked away. I am now looking st a different car and here is where my question comes in. it is a 2005 base model beautiful car I'd post pictures but it's not my car yet so I don't want to make anyone mad. It has a little over 70k miles. Only things done are cold air intake long tubes and exhaust witch is about all I will want done anyway. Here's the thing granted in my silverado it had a lot done to it and was a fresh motor it ran at about 50lbs of oil pressure at operating temp. This car is quite a bit lower At about 30lbs at 210 degrees Everything seems fine with this car and I definitely think it was well taken care of and not abused but should this be somthing I should stay away from or raise a concer?? I just wanted to pick everyone's brain before I jump into anything! Thanks for the feedback!

 

30 lbs pressure at full running temp ( at idle) is fine...My 2005 has 25-26 lbs at running temp at idle and it's never been a problem..Many on here run about the same oil pressure as my car, so I consider this to be fairly normal..More important is that the oil pressure rises as the rpms rise, my car has about 35 lbs pressure at 1300 rpms..You also have to take into account that the oil pressure senders on these cars may not be very accurate...GM states, 10 lbs of oil pressure for every 1000 rpms is considered normal, I don't agree with their numbers completely, but we are both well above those numbers at idle...Higher mileage cars also tend to have lower oil pressure sometimes due to normal wear...I would say your oil pressure is fine, and if all else checks out on the car , and the price is right, to go for it......WW
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The big variables are what weight of oil is in the engine, and the oil temperature.

Our 2006 LS2 and 2009 LS3, when new, with Mobil1 5W-30 and 180'F oil temp, both showed 31 psi at idle and 47 psi at 2,000 rpm.

No numbers on the LS2 as it aged, but the LS3 at 84k miles and same conditions had increased slightly to 33 at idle and 49 at 2k rpm. I suspect that is gauge error rather than an actual increase.

 

Awesome thank you guys for the feedback! I forgot to mention that he has always ran mobile 5w-30. Only thing I didn't check was oil temp but next time I take a look at it I will check that.

 

Remember that it is rpm sensitive.