"Oil pressure low" and "Oil life reset"

polishpickles · January 26, 2016

So I have a 2005 GMC Sierra Hybrid. Had it for about 4 months. It has just under 200k km on it. Took it in for an oil change, and also had both differential fluids replaced, and this one done at a "drive-thru" Castrol oil change place. Everything was ok, until yesterday as I was slowing down to a red light, the truck shut off, then where the kilometers are normally displayed, it said "Oil pressure low" and right after "Oil life reset". I turned the truck off, started it up again and it was fine. Then again same thing happened today after I filled up at a gas station. I checked the oil with the dip stick, seems all good. Called up GMC dealer, mechanic said it could be oil pressure sensor that maybe got "dinged" when the oil was being changed? Another dealer said said it could have been that the Castrol place put wrong oil in the truck and suggested to have another oil change done. The oil they put it was 5w30.

The truck runs fine on the highway, it seemed that it did it at lower rpms when I was slowing down.

What do you guys think the issue could be?

newdude · January 26, 2016

Sensor is up top, behind the intake manifold. No way they could have dinged it. Oil fill cap is up front, passenger valve cover, and filter and plug are obviously underneath. Either the sensor is on its way out, or there is an issue with the filter. I'd personally start with the filter, and put an ACDelco filter on there, and then see what happens. We've had filters fix low oil pressure warnings on newer (2007-2013) trucks.

polishpickles · January 26, 2016

Very interesting. I didn't even think of that. Do you mean certain "no name" brands of filters could cause this problem? I wonder if the sensor is on its last legs, but what are the chances of that happening pretty much right after an oil change?

tbarn · January 26, 2016

Put a PF64 GM filter on it.

polishpickles · January 27, 2016

Sounds like they might have put a cheap or no-name filter in?

newdude · January 27, 2016

Very interesting. I didn't even think of that. Do you mean certain "no name" brands of filters could cause this problem? I wonder if the sensor is on its last legs, but what are the chances of that happening pretty much right after an oil change?

Entirely possible. We just had one of our wholesale accounts run into this on a 2007 new body with AFM. He had a ProTec, or some "budget" brand filter on it, and he would read great oil pressure on start up. Within two minutes, it would read zero. Come to find out, the gasket on it was about two times the thickness than it should have been. He changed it, and problem solved. Right on the chances of that happening. If it is within your abilities, I'd go for the filter and a quart of oil for top off. You will be out $15 tops?

Put a PF64 GM filter on it.

OP's truck is a 2005. Which would be a Gen 3 small block. Gen 3 small block call for the PF46, not PF48. Gen IV small blocks can run PF48, PF48E (which is the current model) and the UPF48R. PF64 is not a Gen IV or Gen V truck filter. PF64 is LT1 (Corvette Camaro), and 2.5 and 2.0T Ecotec engines. Gen V trucks are PF63 (now PF63E).

tbarn · January 28, 2016

Entirely possible. We just had one of our wholesale accounts run into this on a 2007 new body with AFM. He had a ProTec, or some "budget" brand filter on it, and he would read great oil pressure on start up. Within two minutes, it would read zero. Come to find out, the gasket on it was about two times the thickness than it should have been. He changed it, and problem solved. Right on the chances of that happening. If it is within your abilities, I'd go for the filter and a quart of oil for top off. You will be out $15 tops?

OP's truck is a 2005. Which would be a Gen 3 small block. Gen 3 small block call for the PF46, not PF48. Gen IV small blocks can run PF48, PF48E (which is the current model) and the UPF48R. PF64 is not a Gen IV or Gen V truck filter. PF64 is LT1 (Corvette Camaro), and 2.5 and 2.0T Ecotec engines. Gen V trucks are PF63 (now PF63E).

OOps! you are sooo right. my bad.

polishpickles · January 28, 2016

Cool. Thanks for that information 15H. I will look into it and see if I can get an oil change done and do a proper filter if there is a cheap on installed on there right now. If I were to slide under the truck, is it easily visible?

Last question: seems as though the problem hasn't come up in the last 3 days or so. Do you think it was just a weird "glitch" or something? Of is it still better to have the oil and filter changed again?

newdude · January 28, 2016

Cool. Thanks for that information 15H. I will look into it and see if I can get an oil change done and do a proper filter if there is a cheap on installed on there right now. If I were to slide under the truck, is it easily visible?

Last question: seems as though the problem hasn't come up in the last 3 days or so. Do you think it was just a weird "glitch" or something? Of is it still better to have the oil and filter changed again?

Yep. Filter is at the driver's side back of the oil pan.

It is possible that a glitch could be the case. IMO, cheap insurance would be to change at least the filter and see if it happens again. Or, put a few more miles on with the one they put on and see what happens. If you just had the oil changed within the past 500 miles or so, I'd go for the filter. No need really to change the oil again so soon.

polishpickles · February 2, 2016

So far so good. It's been exactly a week since it last gave me that message, but it hasn't done it since. A glitch maybe? I'll keep an eye on it and will change the filter if it happens again. Thanks for your advice!