in2pro

what is your oil pressure gauge showing? may want to have it physically checked also....

73shark

That's a new one for me. Never heard of SBC oil pump problems.

What's your pressure at idle and at cruise speeds?

2008 Suburbanite

It seems to idle around 40 and at acceleration about 50-60. I changed the oil filter again just to make sure it wasn't clogged or a bad filter and it seems like it helped, but the noise is still there. There is probably something damaged--cars don't usually make noise unless there's something wrong with them!!!!

I guess I just need to take it in and have them figure it out--that's what warranties are for!!!!

I am mechanically inclined, but mostly on older cars (muscle cars). These newer, heavy duty vehicles baffle me sometimes. Too much of a pain in the butt!!!!! If I know for sure what's wrong--I can fix it, but I need to know what's wrong first.

Thanks for the help

Chevrolet Customer Service

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This may be related to a lifter issue. I encourage you have the vehicle inspected by your local certified technician. They'll be able to offer an official diagnosis after inspecting the vehicle.

Please keep us posted.

Feel free to contact me privately with any additional questions or concerns.

Louis
GM Customer Service

JPTL

'07 Suburban LTZ w/125k:
While traveling 300 miles from home, I got the low oil pressure/stop engine warning, along with the constant chime. This was the first warning relating to oil pressure. I was used to the low oil level warning....that's a whole different issue.
Of course, I immediately pulled over and cut the engine. Being used to moderate oil consumption w/this V8, I carry a quart or two of oil. Assuming that low oil level was causing low pressure, I added a quart without checking the level. I started it up again, pressure rose to about 35*, and I got back on the highway. I put an asterisk after 35psi, because I hadn't recalled what 'normal' pressure was for this truck. I'll jump ahead here and say that 35psi is lower than normal pressure at highway speeds for my vehicle, but I didn't realize that at the time.
Anyway, after 5 minutes or so, the pressure gauge gradually** dropped, eventually warning again with the chime, but this time the CEL came on as well. This time I pulled over and checked my oil level. 1/2 quart high! WTH? I started Googling "Suburban low oil pressure". Of course all kinds of causes/solutions come up - from internal engine problems; clogged/dirty oil pump screen; dirty screen at the low pressure sensor; bad connection at the sensor; bad sensor; clogged/collapsed oil filter..etc. The fact that the CEL came on, and there was no top end/valve noise had me thinking of some kind of sensor issue, like the low oil pressure sensor...but not knowing the code, I was only guessing. I'll admit that the CEL gave me enough of a hunch that this was a sensor issue and not an actual low pressure issue, that I figured getting myself to an Autozone wouldn't kill my engine, so that's where I headed.
The code did relate to the oil pressure sensor - low voltage or resistance..something like that. This confirmed that this was an issue with the sensor...or so I thought.
I drove home, enduring the nagging chime & trying my best to ignore that serious warning displayed on my dash. The 'burb ran as normal, and I had no valve clatter whatsoever.
**I must admit that the gradual fall of the pressure per the gauge had me concerned. Wouldn't a bad sensor cause more of an erratic jump from near 0 to normal, and more of a back & forth reading?
Admittedly, I drove the 'burb around on errands for the next few days, assuming that the issue was a bad sensor, and not low oil pressure.
After a few days I started to prepare for sensor replacement. That's when I read a post somewhere in which a clogged/collapsed oil filter prevented proper flow and caused a low oil pressure situation. I figured WTH, I'll change the oil and filter. I had a Purolator L12222 on hand and was replacing the same. According to the change clock, I had about 15% left before a needed change.
If anyone wanted to bet me a grand that after the oil & filter change, nothing would change and the low oil warning would return, I would've taken the bet.
I would have lost.
The gauge went up to 45psi at startup, and stayed above 40 during all operation. Prior to the change, the gauge hadn't even gotten close to 40.
This was 2 months ago. The oil pressure gauge has never fallen below 30 during engine operation. It reads normal under all conditions.
Therefore this has to have been remedied by an oil change! I can't say for sure that it was a clogged/collapsed filter, but what else could it have been? I should have kept the filter & cut it in half to see what the insides looked like. My guess would be something very abnormal.
I can also figure that the oil pressure reading was correct! Pressure was in fact dangerously low when it said it was. I hope the hell I didn't do significant engine damage from driving it 150 miles back from my trip, then around town for a few days. I guess time will tell. Good thing this is a time-tested, beefy V8 and not a small, efficient 4 cylinder. I'd probably be leaving clouds of smoke at this point.
Anyway, that's my story. Hopefully this lengthy writeup will help someone along the way..or on the side of the road:
Change your oil as a diagnostic measure and don't rule out a bad oil filter

in2pro

Good info and thanks for sharing... you may save someone some trouble

73shark

And next time, I recommend using an AC filter.

2008 Suburbanite

First off, i want to thank everyone for their ideas and input.

Second--I took the car into the Chevy dealer Thanksgiving week and they had it for over a week.

They eneded up rebuilding the engine--a top end where they replaced everything along with the oil pump. They found wear/tear in #4 & 6 cylinders along with other issues.

Anyway, after about $6,000 or so worth of build, I got the car back. The oil pressure is about 60 all of the time and is running good so far.

I didn't have to pay one cent for it--they used the drivetrain warranty so it covered every bit of it.

Thank you to Bankston Chevy here in Fort Worth for all of their help.

I said there was something wrong since engines don't make noises unless there is something that is wrong with it.

Thought I'd let you all know

Thanks again

JPTL

Second that on the AC

2008 Suburbanite

Also, They found the internal cam shaft to be the main cause of the ticking noise coming from the engine.

Anyway, I thought you all should know.