Low oil pressure on 2007 Suburban.
2007 Suburban. 100k miles, but only driven about 4k miles in the last year.
No oil leaks on garage, and doesn't burn oil. Runs great. No noises or
anything. Checked yesterday and needed 5 quarts. Today, low oil pressure
light came on.
If it needed 5 quarts in an engine that only has 6 when full chances are that you have damaged the bearings already, they could be just leaking pressure right by them thus the low pressure light. You should run a manual oil pressure test to be sure it is not a malfunctioning gauge or sender. So if there are no external leaks then the only place the oil can go is through the engine, so it has to be burning oil, the catalysts when they are functioning properly will take care of oil in the exhaust so you won't see it but it changes the way the exhaust smells.
I agree with Tennisshoes, 5 qts needed in a 6 qt system usually means damage. Get the pressure tested, if it tests out low something (oil pump or bearings) is likely damaged. If the oil didn't leak out it either went out the tailpipe or wasn't filled to the proper level during an oil change. Oil just doesn't vanish. Good luck with it.
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