DexCool in GM Engines

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Same problems with DexCool 4 year old car with less than 14000 miles and coolant is brown instead of red and foul odor inside car. Dealership has same shoe box answer that GM has no problems with Dexcool want me to spend $400 on a new cabin air filter and reprogram car computer so fan runs longer. They also said it might fix problem no guarantees. Why should I have to pay for a reprogram when GM has created the problem. Other forums say the smell comes from heater hoses breaking down on the inside thus causing a foul dead animal smell in car.

I have a 2000 Silverado 1500 Z71 with 5.3 L and 165000 miles that I inherited from my brother about 6 years ago. He bought used in 2006, then has regular antifreeze in it. I'm not sure who put the regular antifreeze in it to begin with, since my brother isn't living and I can't ask, but my radiator and engine doesn't have rust or sludge. I can say my truck overheated from a malfunctioning thermostat about 4 1/2 yrs. ago and I replaced the thermostat and added the 50/50 antifreeze. I did not see any rust anywhere. So, as for the DexCool, I don't know, but I do know my brother was a diesel mechanic, so either he removed the DexCool or GM did. Whomever it was did the right thing because I do not have rust or sludge.

I also have to say I have been a Shadetree mechanic for 30 yrs. and have used distilled water in my radiators for at least 25 yrs., after replacing a radiator and water pump due to rust and failure. Since I started using the distilled water instead of tap water, I have never had rust show up in my radiator water nor have I had to replace a radiator due to clogging. I also only replace my antifreeze every 3 or 4 yrs. So as for old coolant causing problems I think that's crazy.

Intake manifold gasket failed after 12,006 miles on my new 1998 Chevy 454 engine, moho. Called dealer, was told that they were pulling all DexCool from these engines due to intake manifold failures due to the long term DexCool coolant. Since I was over the warranty mileage I was on my own. I replaced the intake manifold gasket, installed standard coolant. I now have 125k miles and 17 years with no further problems. 10 years ago I purchased a 96 Eldorado with the Northstar engine, 75k miles. I had to rod out the radiator, remove the DexCool, replace the water pump, replace the thermostat and install green coolant. 145k miles now. No further cooling problems. 94 Chevy 2500 truck 350, green coolant, 175k, no problems. I won't put DexCool in any engine I own.

In July of 2014 I had my 2000 Pontiac Firebird radiator flushed due to the DexCool being a brown rust color. Recently I had my oil changed and the mechanic recommended I have a coolant flush and that it was really bad. My question is: Is it normal for the DexCool to turn brown and rusty looking and will it harm my vehicle?

My 1994 Firebird will leak between the block and the coolant intake behind the water pump after a couple/3 years, because the remnants of old Dexcool continue to make the Peak antifreeze look dirty and eat the manifold gasket. Annual cooling system flushes and a radiator replacement haven't prevented this gasket leak, and I am removing the power steering bolts and other accessories and brackets to replace the gasket yet again. I will continue to use the green ethylene-glycol 50/50 antifreeze and hope that this time will be the last time that old Dexcool contamination in the block is constituted at a harmful enough level to attack the gasket.

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I have a 97 S10 that has had ALL recommended service intervals done when required, which included changing the antifreeze. At 191,000 miles, the engine went into overheat rapidly and was towed to a shop where it was discovered it had a blown head gasket. It also had a 40% clogged radiator, rust and sludge in the engine block, etc. DEX is the cause of this, according to my ASE certified mechanic. I don't know where GM engineers learned their trade, but it was definitely not at Georgia Tech, because you see at Tech, we were trained to look for causative factors. Since this DEX problem seems to be very prevalent in GM cars, to deny it is akin to a total lack of veracity on GM's part.

I just bought a 2003 buick park avenue ultra back in october. Since then I noticed my car would overheat when the heater wasn't on. I thought it was from driving the engine too hard so I changed the oil and checked the fluids. Me being a mechanic in training could not detect an immediate problem so I drove it as normal until back in December of 2014 the car overheated on the highway!! I later took the car to my dad to have it looked at. Upon examination he told me I had a broken intake manifold, he having had a buick park avenue had the same problem with his car! So I figured I could save up money to have it professionally repaired. However due to other financial difficulties I had to put it off. But suddenly last monday my car started smoking under the hood. I went to a buick dealership to have them look at it but they refused to even look at it!!

So I went online to look up how to repair it myself and I came across numerous articles about other park avenues having the same problem as well as other GM cars with the same engine! And guess what they all had in common, DEXCOOL!!! That stuff has been destroys thousands of GM cars including my Dad's park avenue! I checked the service history and the car having been serviced at a buick dealership its whole life thus meaning DexCool was the fluid used to service the coolant system! I've currently checked the car's coolant tank and have noted DexCool inside the tank prior to the car's last service. I'm angry at both GM and DexCool, and I'm shocked and appalled at how careless, stupid and inconsiderate they are!

I have a 2001 Chevy Lumina and the intake gasket has to be replaced because the Dex-cool coolant eats away at the intake gasket. Many people have had the same problem and I'm positive I wont get another Lumina again.

Got the car from my girlfriend's grandpa. It is a 1997 Buick Lesabre 3.8L, had dex-cool in it, and I asked her brother, "Is this stuff good?" He said yes it's supposed to be in there. Well finally one morning, I was driving and BOWWWWW BOOOM. I thought to myself, what in the hell was that? I got home and the battery gauge went to 8 very quick then had no power steering. Well lucky I was almost home so I parked it and popped the hood. To my surprise, the whole pulley from the water pump came off just sheerd off I had dexcool in the car and before this happen, Buick had said my pump was leaking an intake was as well so they did the work and put dex-cool back in there. I got home, drained it all out, flushed it, and put real stuff in there. Prestone never will that dex crap go in my car. Crap. Stay away.

I currently own a 1996 Pontiac Grand Am which has had numerous problems concerning the dex cool antifreeze. I have had to replace the manifold gaskets twice on this vehicle, and the water pump twice also. I had my system flushed out numerous times which also included a new radiator and also the valve cover gaskets as well as new thermostats 4 times because of over heating. The mechanics all told me there is sludge from the engine that is clogging up my system due to the dex cool. I did contact the Garden City Group in Dublin Ohio in May of 2009. At that time I submitted my bills for these items and to this day I have not heard from them at all.

In 2011 I bought a 2000 S10 for $500 w/ 74,000 miles and a cracked engine and a big hole in the radiator. To be fair, the previous owner HARDLY EVER serviced it. She called me crying "There's smoke and steam pouring out from under the the hood!" I bought a NEW -- not reman -- engine from G.M. and installed it along w/ other new parts (I'm a retired import tech). After 2 trips to N.Y. from FL. (6000 miles) the engine lost ALL oil pressure! This was due to improperly installed camshaft bearings. The dealer's only legal obligation was to provide me with a new engine. However G.M. (after seeing I installed the 1st engine correctly) paid for the labor. They told me specifically to use Dex-cool or risk voiding my warranty (3 yrs - 100,000 miles). Now, to be fair, I'm 1 of those CRAZY people who drains and refills my cooling systems w/ a 50/50 mix of coolant and DISTILLED (NOT TAP) water EVERY year. As a retired tech I'd recommend you do the same (and learn to do it yourself, it's not that hard). That way, the coolant that's in your engine is never more than a year old and rust and corrosion NEVER have a chance to form (and Dex-cool NEVER has a chance to gel or harden up). In my 30+ yrs 5 yrs -- 150,000 miles on ANY coolant is a fairy tale.

I have a 2006 Pontiac Torrent and love it. Bought used with 40k and now have 170k on it. Well maintained. Leaking coolant and have read several sites about GM gaskets and Dex-cool. So... went to dealer. They are aware but nothing can be done. Hmmm, leaking coolant and dealer see bad head gasket. I ASKED IF ANYTHING ELSE IS WRONG OR SHOULD BE DONE at this time. They looked it over… all good. RIGHT. Week later it’s leaking - this time manifold gasket. Now who pays the price - the dealership not sure me again because same plus labor plus new gasket… Again they just replaced last week. That was a $1100 bill. Pissed off. Oh yeah… any suggestions?? Dealer not given me an answer on this yet. Pending lawsuits out there? I keep receipts.

My 97 Chevy SILVERADO sat for 4 years without cranking. Transmission broke and couldn't fix it due to finances. Had engine completely over hauled 6 years ago at 217,000 miles due to gaskets leaking. Engine looked BRAND new inside. Of course I only will use Castrol oil in it and the name brand lubricants and fluids and I change everything routinely, including flushing Radiator/engine block every 2 years. Transmission broke at 242,517 miles. The other night I changed the oil from it sitting 4 yrs, turned the crank by hand, looked at radiator, dexcool looked great, webby - to drain the gas tank because it has half a tank of 93 octane NON-ETHANOL GAS with four bottles of Stabil gas stabilizer. I said what the heck...I then bumped the ignition switch, starter engaged, and the Engine fired right up. I left it running over an hour allowing thermostat to open and checked for leaks. No leaks and no dry rotted hoses or belt. I am amazed!

However I will still flush all the old coolant and replace with new DEXCOOL & Distilled water. The key to me for a long lasting engine is over the top maintenance and using dependable name brand lubricants and fluids. Plus never ever run ethanol gas in anything older than about 2004 unless the manufacture states otherwise. I have no complaints here except it taking me too long to be able to afford a new transmission due to health reasons.

Bought a 1997 monte carlo in 2002 from original owners. Only had 70,000 miles on it but within months of buying it had to replace intake manifold gasket. Then within probably 4 years had to have same thing done due to dex-cool antifreeze. Now have a 2002 Pontiac Grand Prix with a little over 110,000 miles on it and having same problem with it.

2000 s10 Blazer, one owner, 98000 miles. 2007, at 66000 miles, heater core plugged. Radiator looked gunked up. Flushed system and went green peak anti freeze. Ended up changing radiator and heater core due to leaks. Now have rear intake gasket leak. Have 91 Silverado, replaced engine in 2001, cracked oil rings. Had 87 Astro. Changed engines, cracked oil rings. Coworker, 87 c1500 changed engines, oil burning, probably same thing. Brother, 88 Astro Jayco package, bought new, warranty just expired. Cracked oil rings. Changed engines. I also have 2004 Trailblazer with 130000 miles. Engine still seems good but burnt tranny fluid and changed ignition switch twice. GM quit making quality cars in the early 80s. Sorry GM. Won't buy another unless it comes with a lifetime bumper to bumper guarantee.

My 2001 camaro. I got it brand new, and have had nothing but problems with it. It has always ran at 190 degrees or more and had many repairs. I am the only driver and my kids say I treat it better than them. I just now have 60,000 on it and it's broke down again.

Bought a Silverado used not long started having trouble with heater. Now I learn about the Dex-Cool problems and intake gasket problem.

I brought my first brand new car 2005 Chevy Equinox at around 15000 miles had to have new rotors and brake completely redone. Then about 50,000 miles, had to have the head gasket replaced due to overheating. It has never ran good since. Now at 80,000 miles, it is overheating again and to be honest, I am about ready to take a sledge hammer to it and I am just taking about the major thing. I have driven beaters my whole life and have driven them into the ground and never had so much problems as I have had with this car!!!! Now I am sitting here trying to scramble around and borrow a car to get to work :( And shaking my head. I will probably never be able to buy another brand new car. Guess I will go back to driving a beater. Don't buy a Lemonox 2005, it will bring you to tears.

I have a 2002 Chevy Cavalier, um, it's the coolant... Blown head gasket radiator. I'm debating right now to junk or fix.... I have the parts but the labor. As soon as I put the coolant that night, it was running hot over 200.

My beloved 1999 Chevy Venture van with 3.4 V6 engine failed on April 18, 2013 at 152,850 miles. It experienced sudden loss of power in construction zone on I-57 near Chicago and was towed in. Spark plugs and wires were recent so mechanic checked for lack of fuel problem and ruled that out. Venture was started and engine and it shook violently and was diagnosed as lower engine failure. Due to blown intake manifold gasket failure which allowed antifreeze into the engine oil, which attacked bearings and ruined lubrication of the engine oil; which ruined bearings where piston rods attach to crankshaft. Mechanic said he had seen many blown intake manifold problems with Chevrolet 3.4 V6 and other Chevy engines and problems are publicized all over the Internet, as well as problems with DEX-COOL.

I went online and was shocked to learn the extent of financial loss to so many GM and Chevy owners. HAD I KNOWN about this issue, I would not have invested in a rebuilt transmission and new radiator 5 months earlier. On Dec 24, 2012 at 151,326 miles, transmission failed on I-65 near Chicago and was towed in. Failure due to 50% restriction in radiator ATF cooling tubes. Transmission rebuilt and radiator replaced at cost of $2,889. On June 7 2012 at 148,564 miles, engine was losing coolant so intake manifold gasket was replaced at cost of $724. On Oct 10, 2010 at 139,196 transmission rebuilt due to hard shifting at cost of $1,392. On Sept 24, 2010 at 138,397 miles engine was overheating, so cooling system flushed and refilled with DEX-COOL at cost of $145.58. On April 19, 2002 at 68,435 miles, intake-manifold gasket replaced first time at cost of $701. On Jan 25, 1999, we purchased Chevy Venture van, took good care of it and expected engine to reach 200,000 miles.

I took good care of my Venture and expected engine to make 200,000 miles with no problems. Additional repairs listed: New plug wires at 152,389 cost $201. New muffler at 151,889 cost $96. Throttle body repair at 151,009 cost $175. New front brakes at 149,354 cost $150. Headlight at 145,982 cost $246. Two tires at 141,061 cost $139. New spark plugs at 134,499 cost $150. Oil changes at 151.012-148,546-145,140-138,053-135,356-132,083. Please publish address of where to send my documentation so executives at GM, Chevy, DEX-COOL know about turmoil and financial loss of poorly-engineered intake manifold gaskets and DEX-COOL antifreeze. I hope to get in on next class-action lawsuit.

GM 3800 Motor - Everyone should have been notified of this problem. My only means of transportation burned to the ground because of this Dex-cool / manifold problem. I bought this car brand new off the lot (quite a few years ago) but was never notified of any sort of problems like this. Now, not only did I lose my transportation, but I have some home damage as well. Spontaneous combustion is what it seemed like, right in my garage. GM should own up to this.

The intake gasket on my van which is a 1999 Chevy Venture failed and the head gasket failed three times.

I took my SUV in for service in October 2012 and I was told that I needed to replace head gaskets. I contacted GM Customer Service. I was given a case number and referred to a local dealership. After taking the SUV in, they told me and my brother-in-law that I didn't need a head gasket but replace the antifreeze and they charged me. When I noticed that the engine light is on again and the antifreeze was leaking again, I contacted the same dealership. I took it in and was told that now I need head gaskets. I contacted GM again in March 2013 and was given another case no. I was told they would check into the matter. Today, I was told they couldn't help me. General Motors and that Chevy dealership should have repaired that head gasket the first time. The model has been a problem for many car owners with complaints of replacing the head gaskets because of the coolant Dexcool used!

I also have the whole Dex-Cool issue. I'm not sure if I have the gasket issue yet (I sure as hell hope not). But I've noticed the sludge in my radiator. But for everybody that hasn't been completely screwed or those of you that have but don't know what to do, flush your system fully and go back to the ethylene glycol coolant we all know and love. It will work the same without all the major damages.

We have a 2002 Chevy Impala with 42,000 miles and just two weeks ago, a mechanic found this gooey stuff (dex-cool) in our radiator. It was in the oil, the gaskets, and other places costing us $1,110. I called GM and they told me I should have taken it to a GM mechanic which by anti-trust laws this is wrong. I can take it where I want. We are both in our late 80's and now GM will do nothing to repay us for any repair we had done. Is this fair? My husband has cancer and we do not have a lot of money, so every penny counts with us.

I own a 2003 Malibu and the manual states to only add DexCool. Well, this is what I have been doing for 9 years and now for the past two years, I have been experiencing nothing but problem after problem. First, it was the water pump then it was the radiator needing to be flushed, now I need the gasket replaced. At least two times a week, I have to add coolant and this is very annoying.

I found a mechanic who can repair but I’m not sure if I want to spend that much money on a car that is 10 years old. But I also do not want a car payment right now. GM sucks. I will not buy another GM car because they are built to keep people paying with their cheap plastic parts. My next car will be a Toyota or Honda because American-made cars just want to keep ripping off Americans with their high price, plastic parts, faulty electrical systems; cars that begin to break down within 5 years.

I have a 2001 Buick Century with a terrible radiator sludge issue and a leaking Intake Manifold and seals, all due to a manufacturer defect involving faulty design of the Intake Manifold and its interaction with the corroding Dex-Cool coolant which was factory-installed by GM. My manual specifically states owners need to keep Dex-Cool in their radiators. I only just learned of a class action lawsuit against GM which happened in 2008 and a settlement which was named the "Dex-Cool Settlement." I had moved in 2008 and never received notice of the class action lawsuit.

When I called GM Customer Relations two weeks ago (October 2012) to tell them about the problems I was experiencing which were exactly the problems outlined in the 2008 lawsuit, they said they'd try to assist me, and told me to have the car diagnosed by a certified Buick mechanic at our local Buick and GM dealership. I followed their advice and unfortunately, much to my dismay, now after the car was diagnosed, the small radiator leak has become a gushing hole, and my radiator does not hold the fluid! I now have to fill my radiator with one gallon of fluid every time I get into my car, rather than every couple of months as I had to previously.

To make matters worse, GM Customer Relations now says they won't help pay for repairs on what is obviously a manufacturer defect. GM only made the problem worse by making me get it diagnosed at their dealership. Now the service manager tells me that it often happens that during their diagnosis of the Dex-Cool radiator sludge and intact manifold problem, the problem gets worse because they add extra pressure to the system. No one at GM Customer Relations or at the dealership forewarned me that this would happen!

I am livid! I resent now being forced to add a gallon of fluid into my radiator every time I get into the car. GM corporate and the dealership mechanic need to do the right thing and pay for the repairs, which they estimated would be about $1200. Not only is GM continuing to damage their reputation, they are about to lose a whole extended family of long-time customers. Shame on them!

DexCool is a mechanic's best friend. I have a 2002 GMC Sonoma. At the 72,000 mile mark, the head gasket went bad; fixed that only then have the radiator go bad. Then the water pump gasket went bad. It is to the point now, with all the problems this truck has given us, we are afraid to drive it very far. We had two other GM products that were also problems. We replaced those GM products with something other than GM. We used to be a GM loyal customer; not anymore. No more GM's for this family.

I just found out about the GM Dex-Cool problem from my shop. This is totally not right. I can't afford to pay $1k for a new gasket. I was always told to buy American. Now I understand why people are not trusting American made cars. It's because they don't stand behind their products. Thanks, GM.

GM's fault. I have a 2000 Buick Century. I bought it new. It has 60,000 miles. The Dex-Cool ate the head gasket and it cost me money to get it repaired. Am I to get reimbursed for this?

DexCool in GM Engines Company Profile

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