I recently replaced my oil pan on a 07 GMC, Yukon, Denali, and when I put everything back together and started the vehicle, it is saying low oil pressure turn engine off, I deleted the code and it’s still coming back and now it has a tapping noise at the top of the engine Which I’m guessing is because it’s not getting oil to the top of the engine, my guess is that the pick up tube is up against the bottom of the pan and not allowing it to suck the oil up or it is really clogged from sitting a couple of days with no oil in it . Can anyone help me with this? It would be much appreciated.
Low oil pressure
- Thread starter Tjudd
- Start date
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Why did you change the oil pan? Did you drop pickup tube and do the very common problem, o-ring for the pickup tube? Did you drop tube and clean it out or replace it? If you replaced, did you compare to the old tube assembly. Sometimes on higher mileage engines, if you let sit for that long with no oil in there and gravity takes over, oil pump loses prime but that is just a guess. Is the oil filter full? Did you remove to see if oil runs out when loosened and does the filter have old oil in it?
Why did you change the oil pan? Did you drop pickup tube and do the very common problem, o-ring for the pickup tube? Did you drop tube and clean it out or replace it? If you replaced, did you compare to the old tube assembly. Sometimes on higher mileage engines, if you let sit for that long with no oil in there and gravity takes over, oil pump loses prime but that is just a guess. Is the oil filter full? Did you remove to see if oil runs out when loosened and does the filter have old oil in it?
It's possible (probable?) that your oil pump lost prime during the process. There is a plug on the driver's side of the block near the front where a mechanical oil pressure gauge can be attached. But it can also be used to backfeed fresh oil into the oil pump to restore prime. I would do that and then turn the engine over by hand several turns with 1-2 quarts extra oil in the sump before starting the engine again.
Dustin Jackson
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@Geotrash I would say it is possible but I think that is a stretch man. My tahoe had the oil pan out for about a month and I buttoned it back up with a new oil pump and it did a good job priming itself, his oil pump should have retained enough oil inside it to fulfill any priming requirement.
@Tjudd There shouldn't be any reason your pickup tube is flush against the bottom of your oil pan and it would need a near vacuum seal to cause low oil pressure in that situation. Best bet is drop the oil pan again and start over, maybe you left a rag or paper towel in there? Did anything else eventful happen during your oil pan gasket replacement?
@Tjudd There shouldn't be any reason your pickup tube is flush against the bottom of your oil pan and it would need a near vacuum seal to cause low oil pressure in that situation. Best bet is drop the oil pan again and start over, maybe you left a rag or paper towel in there? Did anything else eventful happen during your oil pan gasket replacement?
Next time you have your oil changed at a shop, ask the tech if they've ever had an engine not build oil pressure after a change. You might be surprised at what you hear. It's not common, but it does happen. It happened to me once after an oil change on a well-worn Ford 302:
Plimbob
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@Tjudd, I had to replace the timing chain, tensioner, gears, oil pump and pan gasket/oil pick-up ring on my 07 Tahoe. On the initial start-up I had an issue with the lower oil pressure than normal. As it turned out, the Purolator oil filter I used did not pressurizing properly. I replaced with ACDelco filter and after about 4-5 minutes the oil pressure rose to acceptable level at idle (37-42lbs) and has been that way since (12 months ago). Just a thought.
