Oil Weight?
Thread Starter
Burning Brakes
Joined: May 2004
Posts: 816
Likes: 0
From: Bremerton Wa
St. Jude Donor '04 &'05
Oil Weight?
What is the heaviest engine oil you recommend running in a L98. I ran 20w50 in my LS1 Mobil 1. It saw many 1/4 mile passes. I was wondering what everyone thought.
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
20w50? in a modern engine? wow. brave man.
I would go no more than 10-40.
The internal tolerances of the modern engine means that the oil cannot always get past the rings or bearings.
I have a 92, it recommends Mobil 1, 5-30 and thats what I use. Except this time... I could not find Mobil 1 anywhere, so I used Valvoline Synpower... their brake and powersteering fluids are nice, why not the oil?
I would go no more than 10-40.
The internal tolerances of the modern engine means that the oil cannot always get past the rings or bearings.
I have a 92, it recommends Mobil 1, 5-30 and thats what I use. Except this time... I could not find Mobil 1 anywhere, so I used Valvoline Synpower... their brake and powersteering fluids are nice, why not the oil?
Race Director
Joined: Jul 2004
Posts: 16,795
Likes: 62
From: Lake Havasu City, AZ
boundary lubrication is critical in modern tight tolerance engines. you need to ensure therefore that the lubricant quickly gets to the furtherst parts in the engine as quickly as possible.
5W30 is my preference in these circumstances. I personally would never consider going higher than 10W40
5W30 is my preference in these circumstances. I personally would never consider going higher than 10W40
Advanced
Joined: Feb 2004
Posts: 51
Likes: 0
From: Mission Viejo CA
As an electrical engineer paying respect to the engineers at GM
GM spent lot of $$$ determining that my 1996 should use either 5W-30 or 10W-30 Mobil 1. They believe that the film strength and viscosity as well as other characteristics of the above mentioned oils will protect engines as well as maintain performance.
Point being: Higher viscosity oils (anything "thicker" than 10W-30) may actually reduce durability in cold climates as it doesn't flow as well; as previously mentioned.
In summary: Use what the manufacturer recommends in this area. Lubrication technology as well has come a long way even in the last eight years or so...
Just my 2 cents worth....
Point being: Higher viscosity oils (anything "thicker" than 10W-30) may actually reduce durability in cold climates as it doesn't flow as well; as previously mentioned.
In summary: Use what the manufacturer recommends in this area. Lubrication technology as well has come a long way even in the last eight years or so...
Just my 2 cents worth....
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
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
Thread Starter
Burning Brakes
Joined: May 2004
Posts: 816
Likes: 0
From: Bremerton Wa
St. Jude Donor '04 &'05
The car says 116,000 miles but the motor and car are not matching numbers so it is hard to say how many miles are on it.
I used the heavy oil in the LS1 because of the Ring problem they have. My 98 didn't burn much oil but my 2001 burned quite a bit. The heavier oil slowed the burning down. It was that or have Chevy pull it apart and put only 2 new rings on each piston.
I used the heavy oil in the LS1 because of the Ring problem they have. My 98 didn't burn much oil but my 2001 burned quite a bit. The heavier oil slowed the burning down. It was that or have Chevy pull it apart and put only 2 new rings on each piston.
Drifting
Joined: Sep 2003
Posts: 1,483
Likes: 4
From: middle TN
Yep, it appears the newer the engine, the thinner the recommended oil. Was shocked to see that my wife's new Honda CRV gets 5w20 oil. Some new mfgs even recommend 0w20. Sure enough, you'll find it right there on the shelf at Walmart.
Thread Starter
Burning Brakes
Joined: May 2004
Posts: 816
Likes: 0
From: Bremerton Wa
St. Jude Donor '04 &'05
The 03 Cobra recommends 0w20. You can only get it at the dealer around here.
I will go with 10w40 then. My gas mileage sucks anyway...The car has headers, exhaust, custom chip and who know what else, it sounds like it has a cam. Hard to say, but it won't run with a stock L98 chip.
I will go with 10w40 then. My gas mileage sucks anyway...The car has headers, exhaust, custom chip and who know what else, it sounds like it has a cam. Hard to say, but it won't run with a stock L98 chip.
Race Director
Joined: Dec 2002
Posts: 13,348
Likes: 233
From: SCMR Rat Pack'r Charter Member..Great Bend KS
Originally Posted by bogus
20w50? in a modern engine? wow. brave man.
I would go no more than 10-40.
I would go no more than 10-40.
10W-40 is 10weight oil.
The difference between 20W and 10W is so slight that it takes precision intruments to detect it.
So...while I would go with what the factory recommends, moving up to 20W-50 is not going to kill your motor. If you have a valid reason for using it, as the original poster seems to have, use it and stop worrying.
Larry
code5coupe
Safety Car
Joined: Feb 2001
Posts: 4,397
Likes: 0
From: Looks like I picked the wrong week to stop sniffin glue Orlando
We’ve used 20-50 in all our vehicles for the past 30 years. From the day we bring it home till the day we sell it we’ve never had a problem, and we keep cars for 7 to 10 years on average, sometimes longer.
You want to know why manufactures are using lower viscosity oil? EPA they get better gas mileage with thinner oil.
Next time you take an out of state trip use heavy oil on the way out and note your mileage. Have the oil changed at your destination with the thinner oil and compare notes when you get back
You want to know why manufactures are using lower viscosity oil? EPA they get better gas mileage with thinner oil.
Next time you take an out of state trip use heavy oil on the way out and note your mileage. Have the oil changed at your destination with the thinner oil and compare notes when you get back
