Changing DEX-COOL Coolant
Thread Starter
Intermediate
Joined: Nov 2002
Posts: 38
Likes: 0
From: Edwardsville Illinois
Changing DEX-COOL Coolant
I recently purchased a ’96 Collector Edition, with just under 9400 miles. From all appearances, the vehicle has been well cared for. The only concern I have is about the DEX-COOL engine coolant. I have not yet been able to find out if the coolant has been changed since the car was manufactured. The owner’s manual says that the coolant is designed to remain in your vehicle for 5 years or 100,000 miles, whichever occurs first. The car was purchased new in September ’96; consequently, the Corvette is 7 years old. I am in the process of trying to find out if the coolant has been changed and if it has not, I am going to change it. If I do change the coolant, I will also do a coolant system flush.
I have read some horror stories on various websites about the DEX-COOL coolant. If the coolant has not been changed in 7 years, what concerns should I have and what might I want to do to possibly help avoid any problems from the coolant not having been changed.
I have read some horror stories on various websites about the DEX-COOL coolant. If the coolant has not been changed in 7 years, what concerns should I have and what might I want to do to possibly help avoid any problems from the coolant not having been changed.
Drifting
Joined: Mar 1999
Posts: 1,250
Likes: 1
From: Greensboro NC
Re: Changing DEX-COOL Coolant (CE King)
Dex Cool is fine if you change it in the recommended intervals because it loses its ability as a corrosion fighter and the system begins to rust. This becomes evident by the brown scale or sludge in the overflow first and then proceeds to contaminate the entire system and radiator.
I had this start to happen in my 96 vette in 2002 and just flushed the system and refilled with dex-cool. No problems since.
Lots of people don't like dexcool, but if the system is properly maintained there are no problems with it. Don't even mix with the green stuf.
I had this start to happen in my 96 vette in 2002 and just flushed the system and refilled with dex-cool. No problems since.
Lots of people don't like dexcool, but if the system is properly maintained there are no problems with it. Don't even mix with the green stuf.
Melting Slicks
Joined: Oct 2000
Posts: 2,491
Likes: 1
From: prescott AZ
Re: Changing DEX-COOL Coolant (Alex D)
Why take a chance. Use steam distilled water (not distilled by ionization) and flush the system. i just did this on my low mile 95 but I used the new G-05 anti-freeze (new to us-used for years in Europe in Mercedes). This anti-freeze is now factory fill for the new Fords and Jeeps. It can be used with any concentration of the green (but loses some of its 5yr/150k mile protection) but not with any of the Dex-Cool . It has better corrosion protection than either green or Dex and is a low silicate type so your expensive water pump will last longer. I researched this well before i put it into my baby. Auto Zone sells it. It is more than the other stuff but you get what you pay for.
Melting Slicks
Joined: May 2001
Posts: 3,270
Likes: 26
From: Winchester VA
Cruise-In V Veteran
Re: Changing DEX-COOL Coolant (CE King)
I work at a dealership and in two years at 50 cars a day have never seen Dex-Cool CAUSE a problem. I have seen customers with coolant leaks running with low coolant for months and how that has a negative impact on the cooling system overall. I wonder how many horror stories are about vehicles that were properly maintained.
I would suggest going ahead with the flush if you don't know that it has been changed. It's a low cost easy job that will give peace of mind.
And, enjoy the new ride :cheers:
I would suggest going ahead with the flush if you don't know that it has been changed. It's a low cost easy job that will give peace of mind.
And, enjoy the new ride :cheers:
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Re: Changing DEX-COOL Coolant (Ski2Tee)
Isn't the change 100K OR 5 YRS? I got about that out of my driver (an S10), The waterpump failed at 55,000, but the Dex Cool was about 4.5 years old, so I guess I got my money's worth.
Safety Car
Joined: May 2002
Posts: 4,010
Likes: 26
From: Somewhere nowhere
Re: Changing DEX-COOL Coolant (Ski2Tee)
>>I work at a dealership and in two years at 50 cars a day have never seen Dex-Cool CAUSE a problem. I have seen customers with coolant leaks running with low coolant for months and how that has a negative impact on the cooling system overall. I wonder how many horror stories are about vehicles that were properly maintained.
<<<<
then how come my 96 impala had 5 heater cores clog up?
<<<<
then how come my 96 impala had 5 heater cores clog up?
Melting Slicks
Joined: May 2001
Posts: 3,270
Likes: 26
From: Winchester VA
Cruise-In V Veteran
Re: Changing DEX-COOL Coolant (larryfs)
>>I work at a dealership and in two years at 50 cars a day have never seen Dex-Cool CAUSE a problem. I have seen customers with coolant leaks running with low coolant for months and how that has a negative impact on the cooling system overall. I wonder how many horror stories are about vehicles that were properly maintained.
<<<<
then how come my 96 impala had 5 heater cores clog up?
<<<<
then how come my 96 impala had 5 heater cores clog up?
I have alot of experience and knowledge to share and try to when it's pertinent. You had an experience to share but instead you get smart with me, real nice tough guy :rolleyes:
Oh yeah, your advice I'm sure was invaluable to the original poster, do keep it coming.
[Modified by Ski2Tee, 11:26 PM 10/25/2003]
Safety Car
Joined: May 2002
Posts: 4,010
Likes: 26
From: Somewhere nowhere
Re: Changing DEX-COOL Coolant (Ski2Tee)
nah, just a wise butt once in a while :jester
actually most impala owners had repeated heater core cloggings with dexcool sludge, but not corvettes nor other LT1 cars. some say it was an overdose of the tablets at the factory, some say the tablets don't belong in dexcool, others have not had a problem.
and I did read an article or two about dexcool forming sludge if it runs low.....
so to the original poster, just coolant, no GM tablets, or other additives...
actually most impala owners had repeated heater core cloggings with dexcool sludge, but not corvettes nor other LT1 cars. some say it was an overdose of the tablets at the factory, some say the tablets don't belong in dexcool, others have not had a problem.
and I did read an article or two about dexcool forming sludge if it runs low.....
so to the original poster, just coolant, no GM tablets, or other additives...
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
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
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
Burning Brakes
Joined: Dec 2001
Posts: 777
Likes: 1
From: Fort Worth Texas
Re: Changing DEX-COOL Coolant (CE King)
I have a 96 LT4 Coupe with 60,000 miles with orginal water pump and I have just changed the Dex-Cool and there was NO sludge. My wifes 94 LT1 TA has over 140,000 miles and I am on the second water pump and I have changed the Dex-Cool two times and never any sludge?? :thumbs:
Race Director
Joined: Feb 2003
Posts: 11,671
Likes: 20
From: Lake Wylie SC
Re: Changing DEX-COOL Coolant (CE King)
Basic rule of thumb: If it didn't come with dexcool, don't change to it. Why? Most people don't really do a complete flush of the entire system. When dexcool mixes with the green stuff, things happen. Some say the seals, especially in the coolant pump, seem to fail earlier than the ones that stay on the green stuff. I also, come from the school of thought that I would not go more than 2 years with any antifreeze. But then again, I change my tranny oil more frequently than most people change there oil. :crazy:
I'm sorry, I see yours is a 96 and they did come with dexcool. Stay with it. Take a look at this: https://www.corvetteforum.com/techti...=222&TopicID=2 might make things easier :cheers:
[Modified by Strick, 9:53 AM 10/26/2003]
I'm sorry, I see yours is a 96 and they did come with dexcool. Stay with it. Take a look at this: https://www.corvetteforum.com/techti...=222&TopicID=2 might make things easier :cheers:
[Modified by Strick, 9:53 AM 10/26/2003]
