2003 Yukon losing ~3 quarts oil over 3k miles

[95escahoe]

Before you go panicking over a rear main seal job, check you oil pressure sender at the back of the intake manifold...lots of guys have gotten the trans out only to realize that their weekend was wasted because of a $25 part...I replaced 2 on my truck...and about 40 on other tahoes/yukons. the way I stopped it was I used the blue devil brand teflon tape because the stuff they use to "seal" the thread from factory is crap....just my .02
A lot of 5.3s do actually need a rear main seal though, definitely want to be 100% before you tackle that job.

Can the oil pressure sender be bad and leaky without the oil pressure moving around or reading bad? Got a leak on the back of my 6.0 was thinking it was the rear main nothing crazy but leaks a tiny bit


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[axekick]

I'm pretty sure you'd notice some oil on the ground if you were leaking 3 quarts between changes. I think you're less likely to be able to tell if its burning some oil. The PCV system could be the culprit, or some worn rings. You could do a compression or leak down test to check the rings. I don't know how to test the PCV system but a catch can would help if that was the problem.

 

[RELEASE2063]

I have an 01 Tahoe with 221k with the exact same issues. I bought an ls6 valley cover and speed engineering catch can to help keep oil consumption down. It has a leak but said leak isn't putting out 3 quarts of oil on the ground. After doing my compression check they were all within 15 psi of each other and within spec. I will let you know when I can get all this put on and start noticing how much it cuts down, I am currently waiting on e-fan harness and Long tubes so I can do all at one time and take and get it tuned. I will keep you posted to see how she does.