Is Dexcool cool or not so cool?
Thread Starter
Instructor
Joined: Mar 2001
Posts: 230
Likes: 1
From: Phila. Pa.
Is Dexcool cool or not so cool?
I've had a few people tell me to flush out all the dexcool and replace it with the good old green stuff. They say the dexcool eats up head gaskets. Whats the story?
Racer
Joined: Sep 2006
Posts: 389
Likes: 1
From: Roswell GA
It is great as long as you don't get air in the system. If you do it can turn to a mud like substance and cause radiator and other parts to get gunked up. Then you will have an overheating car.
Tech Contributor
Joined: Oct 1999
Posts: 41,013
Likes: 9,773
From: Charlotte, NC (formerly Endicott, NY)
Dexcool provides corrosion inhibitors that aren't in the green stuff and since I have never heard of a LS engine having problems with Dexcool I am not willing to risk my engine for a rumor. I just pulled my Ron Davis Racing Radiator out to get speedy dry cleaned out of the fins. It was filled with a 50/50 mixture of Dex and water for 3 years. Outside of radiator was plugged with speedy dry and tire rubber inside was clean. Hoses were in good shape, reservoir was clean and the coolant looked the way it did when I put it in. I refilled with 50/50 mix of Dex and water.
Bill
Bill
Racer
Joined: Sep 2003
Posts: 317
Likes: 5
From: St. Louis Missouri
There are several states with class action lawsuits against GM for the use of DexCool. It has proven to be a problem with head gasket and other components in earlier cars (starteing in 1996). Their was an effort to make it a Federal class action suit but that was thrown out so now the states are taking action as they see fit. If you search the internet for "dexcool lawsuits", there is plenty to read. Right now the recommendation (at least in Missouri) is not to change out the Dexcool until a decision is made.
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Melting Slicks
Joined: Dec 2004
Posts: 2,677
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From: I have to return some videotapes
AFAIK, the head gasket issues were specific to the V6 (3.8L?) applications like the Grand Prix. If Dexcool were chewing up head gaskets in LSx motors everyone on this forum would know it. As other said, keep air out of its and you're fine. Just changed mine after 6 yrs and it looked like new.
Drifting
Joined: Feb 2003
Posts: 1,778
Likes: 1
From: Myakka City Fl
Use Coolant that meets GM Spec
Propolyene glycol based engine coolant may be used in GM vehicles and will not affect the warranty coverage if it meets GM spec. It is less toxic.
OGC5
Tech Contributor
Joined: Oct 1999
Posts: 41,013
Likes: 9,773
From: Charlotte, NC (formerly Endicott, NY)
The DexCool has been in my 2003 Tahoe since it was made in December 2002. The heads are aluminum but the block is cast iron. No problems to date. My wife's 99 Saturn is on its second fill of DexCool with no problems.
People can sue about anything and even win sometimes. It doesn't mean they are right or even know what is going on.
Bill
People can sue about anything and even win sometimes. It doesn't mean they are right or even know what is going on.
Bill
Tech Contributor
Joined: Dec 1999
Posts: 32,910
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Melting Slicks
Joined: Dec 2004
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From: I have to return some videotapes
Le Mans Master
Joined: Sep 2004
Posts: 5,707
Likes: 4
From: Los Angeles
Ok, here's my Dexcool story. I had a problem in 2003 with my 1999 GMC Jimmy. The Dexcool turned into a brown paste. I took it in for a routine radiator flush when it was discovered. They flushed the system and refilled. Everything looked fine for about a year when I checked again and found the brown pasty stuff again. I took it in and they wanted to charge me for a new radiator and engine flush. I talked to the area service rep about it and he told them to just do what they had to do to clean it out good and flush the engine good. They took care of it no charge and I haven't had a problem since. My 2000 Vette has exhibited no problems. No one was able to explain to me at that time why it happened to the GMC and not the Vette.
Team Owner
Joined: Mar 2001
Posts: 25,889
Likes: 7
From: Virginia Beach
CI 3-5-6-7-8 Veteran
I've heard about the lawsuits... but it always seems to pertain to mid 90's GM V6s. My mother let her original factory coolant in her '99 vert go until last summer! That's 8 years, but only 45k. Came out looking just fine.
I recently helped a buddy do a tune up on his '97 w/ unknown history and his came out looknig nice.
I drain and re-fill mine every 2 ears or so. On my GMC Canyon I'll go the 5 years.
I recently helped a buddy do a tune up on his '97 w/ unknown history and his came out looknig nice.
I drain and re-fill mine every 2 ears or so. On my GMC Canyon I'll go the 5 years.
Instructor
Joined: Feb 2004
Posts: 124
Likes: 0
From: Nashville TN
I have a friend who worked for a local Chevy store as a service advisor for 30 years and he said the stuff was crap. GM designed it to last 100K miles but in order to do so compromised its primary objective. If you are going to change your coolant every 20 grand or so (which he also recommends) go ahead and use the stuff. I have used Prestone since my 1st oil change (original owner) and my Z still runs cool and strong and it just turned 120K miles. I also change the coolant every fall.
Drifting
Joined: Jan 2004
Posts: 1,553
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From: st paul mn
