baddream423

i have a 2004 suburban 4x4/awd and recently replaced knock sensors and the original oil pressure sensor. I've been in a hard financial spot for the last year and was not able to do any repairs. a year ago the oil pressure dropped from 40psi hot to 20psi cold with the low oil pressure chime coming on overnight. i was a mechanic in the past for 5 years or so but had to change careers due to arthritis issues so i know that the oil pressure sensors in these 5.3 fail often. I figured mine had failed as it wasn't ticking, knocking or tapping and still doesn't a year later unless you idle it hot for 10-15 minutes and it gets a slight tick which goes away instantly off idle. the gauge shows 20-25 psi at 2000 rpm and I've taken apart the oil filter multiple times and have found no metal flakes. the new oil pressure sensor shows it has no oil pressure. I'm going to drop the oil pan and inspect for metal or copper flakes. I've replaced the pickup tub o-ring about 6 months before the pressure dropped. I've also read that the oil pressure regulator isn't unheard of sticking open in the oil pumps. i can get a new unused high pressure high volume Melling oil pump from a friend for really cheap along with the gaskets to replace it. i only need to keep the vehicle for another 6 months or so as I'm repairing my 2000 Camaro to use as my daily driver again. I'm planning to put it in storage in the next couple years to restore it. I'm in a lot better financial spot but don't have the means to remove the engine to replace it currently. If i put the HV/HP oil pump on do i need to worry about sucking the pan dry as I've been told by people, it has 240k on the engine. i cant get a clear answer from people running a HV/HP oil pump on higher milage engines, all the sites I've gone too talk about those oil pumps on performance engines which mine is very much not.

Gumby22

I don’t expect it would move enough oil to empty the pan unless there’s a serious problem with bearing clearances - and if there were, you’d be getting much worse than a minor tick at idle.

Contact Melling to be sure but I highly doubt using the HVHP pump will cause any problems.

Cusser

Hmmm - oil sender still? I know this is tough to get to at rear center of the engine, but I installed a new one into our 2014 Yukon 3 weeks ago. After I installed that, I was still getting on reading on the gauge and the check engine light, until I pulled off the battery cable, cleared the ECU, then reconnected the cable.