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Oil pressure and gas mileage.

SlimShad3y

New Member
Joined
Sep 4, 2022
Messages
2
Hello all!
I have a 2005 Chevrolet Avalanche Z71 4WD. (396,000 Miles)
It was leaking oil a pretty good bit, so I got the oil pan gasket replaced, oil pick up tube o-ring, oil cooler block off gasket, valley covers, knock sensor seals, and both valve covers. Well after all that, it's still leaking, but once the parts/gaskets were replaced, my oil pressure is higher than what it used to do.
Before repairs: 45psi/Cold - 40psi/Warm - and maybe 45-50 at 1300RPM 50 MPH.
After repairs: 60psi/Cold- right below 40psi/warm and 55-60psi at 1300 RPM 50MPH.
Remember it's still leaking oil after the repairs. And I go 30 miles round trip to work mon thru Fri. Before the repairs, at 50MPH 1300 RPM, for 5 days, it would be a tad bit above 3/4 of a tank.
But now, same speed, same rpm, 5 days, I'm on 1/4 of a tank. I don't see or smell any gas at all, but I smell oil burning everytime I shut the truck off, because of the leak. Is that oil pressure normal now because the o-ring on the pickup tube is replaced? And the gas would be a big help. Any help really is appreciated.
 
When I replaced the o-ring on my 2004 EXT, there was little improvement in the oil pressure.

The oil pressures I was seeing were much lower than those you reported before your repairs.

I do not think I would have even considered any repairs if I were seeing your lower pressures.

I then replaced the oil pump and I now see close to your post repair oil pressures.

I used the Melling M295HV-324S oil pump and oil pick up tube kit.

I suspect your oil leak is the very common rear main seal.

I've also had the rear main seal replaced on my EXT and it stopped my oil leaks.

At it's worst, my leaking rear main seal was allowing oil to leak down and blow back onto the exhaust crossover pipe causing the burning oil smell.

You might want to get that fixed before you catch something on fire.

Your gas mileage could be any number of things, but most likely not related to your oil leaks.

It might be helpful to actually write down and track your actual miles per gallon to see where you actually stand.

Your mileage may actually still be the same, but the fuel level you are seeing is a result of the fuel level sensor going bad in your 17+ year old truck.

That too is not uncommon.
 
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