Coolant Recommendation
Thread Starter
Drifting
Joined: Jun 2000
Posts: 1,872
Likes: 294
From: St. Louis MO
Coolant Recommendation
Switching thermostat this weekend ...
First, how much coolant am I going to lose on an LS3? Second, I've heard not so favorable reviews on the OEM Dexcool ... what recommendations do my Forum brothers have? I'm not planning a complete flush ... so, how much will I need and any issue(s) in mixing new with the OEM stuff???
First, how much coolant am I going to lose on an LS3? Second, I've heard not so favorable reviews on the OEM Dexcool ... what recommendations do my Forum brothers have? I'm not planning a complete flush ... so, how much will I need and any issue(s) in mixing new with the OEM stuff???
Race Director
Joined: Jan 2004
Posts: 18,722
Likes: 708
From: Bergen County, NJ
I just did a complete coolant flush on my 2006, it's 5 1/2 years old and there was no problem with the OEM Dexcool.
There once was a problem with Dexcool where it gummed up, but I understand that was remedied about 10 years ago. Dexcool 50/50 mix is what to use.
There once was a problem with Dexcool where it gummed up, but I understand that was remedied about 10 years ago. Dexcool 50/50 mix is what to use.
Safety Car
Joined: Aug 2007
Posts: 4,836
Likes: 9
From: Rushsylvania Ohio
I have had the stat out twice now on my LS3. I use a cat litter pan (they are low) and slide it under the radiator drain. Drain there first and then slide the pan under the stat housing. Lossen the bolts to the stat housing and pull it back slightly and let the coolant drain instead of just gushing out. Remove housing, change stat, bolt back up. I then use a paint filter and pour the fluid back in. I have a full jug of Dexcool that I have not even had to open yet as I did not loose hardly any coolant using the large litter pan.
One tip on chaning out the stat - don't take the lower hose off the stat housing. Just remove the two bolts and pull back. Much easier to do this way. Make sure the tab on the gasket is lined up with the housing when you put back.
Seems like a major job, but in reality it will take you maybe 10 minutes from start to finish. Make sure car is sitting flat when you put the fluid back in.
One tip on chaning out the stat - don't take the lower hose off the stat housing. Just remove the two bolts and pull back. Much easier to do this way. Make sure the tab on the gasket is lined up with the housing when you put back.
Seems like a major job, but in reality it will take you maybe 10 minutes from start to finish. Make sure car is sitting flat when you put the fluid back in.
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From: Cape Cod, Mass.
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Stick with the GM Dexcool. There are no issues with it. You run into problems when you mix Ethlyn Glycol based anti freezes with Dexcool and end up with a gelatin-like mess in your radiator and motor. Use a 50/50 mix of Dexcool and distilled water. A bottle of Watter Wetter won't hurt.
Racer
Joined: Apr 2006
Posts: 486
Likes: 2
From: The Villages FL
THERE IS NO PROBLEM WITH '' DEXCOOL''! The past bad history was engine specific and was not the fault of Dexcool. Replace it every 5 years or 150,000 miles which ever comes first and enjoy your car.
Team Owner
Joined: Jun 2005
Posts: 46,295
Likes: 2,596
From: Northern, VA
St. Jude Donor '15
"In honor of jpee"
use dexcool, the real stuff.
one of the issues w. dex was if it got low in the reservoir, it tended to foam up a bit and not work as well at cooling. idea/key is to get it right w. no air pockets in cooling syst., and correct level. just watch the level for several times after you drive and cool off.
one of the issues w. dex was if it got low in the reservoir, it tended to foam up a bit and not work as well at cooling. idea/key is to get it right w. no air pockets in cooling syst., and correct level. just watch the level for several times after you drive and cool off.
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Thread Starter
Drifting
Joined: Jun 2000
Posts: 1,872
Likes: 294
From: St. Louis MO
I have had the stat out twice now on my LS3. I use a cat litter pan (they are low) and slide it under the radiator drain. Drain there first and then slide the pan under the stat housing. Lossen the bolts to the stat housing and pull it back slightly and let the coolant drain instead of just gushing out. Remove housing, change stat, bolt back up. I then use a paint filter and pour the fluid back in. I have a full jug of Dexcool that I have not even had to open yet as I did not loose hardly any coolant using the large litter pan.
One tip on chaning out the stat - don't take the lower hose off the stat housing. Just remove the two bolts and pull back. Much easier to do this way. Make sure the tab on the gasket is lined up with the housing when you put back.
Seems like a major job, but in reality it will take you maybe 10 minutes from start to finish. Make sure car is sitting flat when you put the fluid back in.
One tip on chaning out the stat - don't take the lower hose off the stat housing. Just remove the two bolts and pull back. Much easier to do this way. Make sure the tab on the gasket is lined up with the housing when you put back.
Seems like a major job, but in reality it will take you maybe 10 minutes from start to finish. Make sure car is sitting flat when you put the fluid back in.
CF Community Team
Joined: Oct 2004
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From: Cape Cod, Mass.
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Team Owner
Joined: Jun 2005
Posts: 46,295
Likes: 2,596
From: Northern, VA
St. Jude Donor '15
"In honor of jpee"
I agree with Michael, swiftrider, above, but there is also "licensing" of Dex to Prestone and others (see below quote). It gets a bit more expensive at the GM dealer, but for sure it's the real thing.
per this fr. Prestone site (http://www.prestone.com/products/print/411?popup=1):
"Technology
This patented formula has a concentrated blend of premium long-lasting inhibitors for extended performance, protecting against temperature extremes and the ravages of rust and corrosion. Prestone® Dex-Cool® Approved Antifreeze/Coolant has been approved by General Motors to be licensed as a DEX-COOL(r) product under the GM 6277M specification."
per this fr. Prestone site (http://www.prestone.com/products/print/411?popup=1):
"Technology
This patented formula has a concentrated blend of premium long-lasting inhibitors for extended performance, protecting against temperature extremes and the ravages of rust and corrosion. Prestone® Dex-Cool® Approved Antifreeze/Coolant has been approved by General Motors to be licensed as a DEX-COOL(r) product under the GM 6277M specification."
CF Community Team
Joined: Oct 2004
Posts: 19,350
Likes: 5,240
From: Cape Cod, Mass.
2025 C6 of the Year Finalist - Unmodified
2025 C8 Z06/7/E-Ray of the Year Finalist - Unmodified
2023 C3 of the Year Finalist - Unmodified
2021 C8 of the Year Finalist Unmodified
2020 Corvette of the Year Finalist (performance mods)
2019 C1 of Year Winner (performance mods)
2017 Corvette of the Year Finalist
2016 C2 of Year
2015 C3 of Year Finalist
The reality is that most coolants are made by the same manufacturer and re-badged. The Prestone Dex-Cool meets GM specs and I have been using it for years with no issues whatsoever. If you want to pay more for the same coolant, go to your stealership.
Tech Contributor
Joined: Oct 2008
Posts: 1,378
Likes: 11
From: St Louis MO
Switching thermostat this weekend ...
First, how much coolant am I going to lose on an LS3? Second, I've heard not so favorable reviews on the OEM Dexcool ... what recommendations do my Forum brothers have? I'm not planning a complete flush ... so, how much will I need and any issue(s) in mixing new with the OEM stuff???
First, how much coolant am I going to lose on an LS3? Second, I've heard not so favorable reviews on the OEM Dexcool ... what recommendations do my Forum brothers have? I'm not planning a complete flush ... so, how much will I need and any issue(s) in mixing new with the OEM stuff???
Thread Starter
Drifting
Joined: Jun 2000
Posts: 1,872
Likes: 294
From: St. Louis MO
Waiting for my Corvette mechanic to get back in town - doing sways, ceramics & fluid, t-stat. I just had surgery and can't wrench or wiggle in tight spaces.
