Ls1 oil consumption- Good leakdown/compression?
Thread Starter
Instructor
Joined: Aug 2020
Posts: 199
Likes: 15
Ls1 oil consumption- Good leakdown/compression?
2000 C5 has 157k and uses oil much more than the already high rate GM says is acceptable. Spits black carbon out the exhaust, covers the back of the car and stains the concrete.
I did an LS6 valley pan to try to help and was surprised to see I did not need to grind the boss in the valley to clear so perhaps this car has a later engine and who knows how many miles. I've tried every other option to get this under control and now feel that the only thing left is to re-ring it as per the GM TSB which is obviously a significant job.
But I did a leakdown and compression test and got good numbers on all cylinders, could that be and still need to re-ring?
Also the ring kit in the TSB is discontinued, is there a new recommended ring pack or procedure? The TSB cautions against honing the bores and only replace certain rings but digging this far in I would want to freshen everything up.
I did an LS6 valley pan to try to help and was surprised to see I did not need to grind the boss in the valley to clear so perhaps this car has a later engine and who knows how many miles. I've tried every other option to get this under control and now feel that the only thing left is to re-ring it as per the GM TSB which is obviously a significant job.
But I did a leakdown and compression test and got good numbers on all cylinders, could that be and still need to re-ring?
Also the ring kit in the TSB is discontinued, is there a new recommended ring pack or procedure? The TSB cautions against honing the bores and only replace certain rings but digging this far in I would want to freshen everything up.
Tech Contributor
Joined: Jan 2007
Posts: 19,423
Likes: 1,146
From: Dyer, IN
2000 C5 has 157k and uses oil much more than the already high rate GM says is acceptable. Spits black carbon out the exhaust, covers the back of the car and stains the concrete.
I did an LS6 valley pan to try to help and was surprised to see I did not need to grind the boss in the valley to clear so perhaps this car has a later engine and who knows how many miles. I've tried every other option to get this under control and now feel that the only thing left is to re-ring it as per the GM TSB which is obviously a significant job.
But I did a leakdown and compression test and got good numbers on all cylinders, could that be and still need to re-ring?
Also the ring kit in the TSB is discontinued, is there a new recommended ring pack or procedure? The TSB cautions against honing the bores and only replace certain rings but digging this far in I would want to freshen everything up.
I did an LS6 valley pan to try to help and was surprised to see I did not need to grind the boss in the valley to clear so perhaps this car has a later engine and who knows how many miles. I've tried every other option to get this under control and now feel that the only thing left is to re-ring it as per the GM TSB which is obviously a significant job.
But I did a leakdown and compression test and got good numbers on all cylinders, could that be and still need to re-ring?
Also the ring kit in the TSB is discontinued, is there a new recommended ring pack or procedure? The TSB cautions against honing the bores and only replace certain rings but digging this far in I would want to freshen everything up.
- Are you the original owner?
- Any modifications?
- Any codes?
- Live data you can share?
- Fuel pressure? Engine vacuum?
- Any smoke from the exhaust?
- How much oil do you consume in what amount of time?
Racer
Joined: Apr 2019
Posts: 309
Likes: 120
From: Central PA
2024 C5of the Year Finalist - Unmodified
2000 C5 has 157k and uses oil much more than the already high rate GM says is acceptable. Spits black carbon out the exhaust, covers the back of the car and stains the concrete.
I did an LS6 valley pan to try to help and was surprised to see I did not need to grind the boss in the valley to clear so perhaps this car has a later engine and who knows how many miles.
I did an LS6 valley pan to try to help and was surprised to see I did not need to grind the boss in the valley to clear so perhaps this car has a later engine and who knows how many miles.
Last edited by VETTEYOG; May 26, 2026 at 12:48 PM.
Safety Car
Joined: Mar 2017
Posts: 3,768
Likes: 940
From: Orlando Florida
My thinking exactly. 26 year old elastomers, in a not-so-wonderful environment. Also, which head castings do you have? Unless I've mixed up my readings, a 2000 should be 853's, no?
Last edited by redzg; Yesterday at 05:40 PM.
Thread Starter
Instructor
Joined: Aug 2020
Posts: 199
Likes: 15
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo