My experiences with it have all been bad.
I have seen it eat plastic (i.e. Intake manifolds) and silcone (rubber gaskets).
Experiments at other automakers that I was a part of yielded the same.
Dexcool sucks.
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ive never had a problem with it, my 2000 cavalier had it for 100K miles no problem. this one i have now has had it for 60K no problems.
Just for the record, J's are not a victom of alot of these problems as are some other cars.
No coolant goes through the plastic intake manifold as it does on the V8s and V6s.
Many a Buick 3800 has had an intake replaced for this reason.
The only thing that really a potential issue on the J's is the water pump, which 2.4s are real notorious for failing regularly.
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Dex-cool IS a good product in theory. Problem is, the product was too new for use. Not enough people new how to handle and use it. If used as intended in a system designed for it, AND that system was in good condition, it will work as intended. I have a '96 2.2 with 190K+ miles on it. My head gasket did fail due to an assembly flaw, not Dex-cool. The radiator leaked when it cracked at a stress point. The replacement has that point reinforced. My heater core is getting replaced this spring, NOT unusual with any coolant. Otherwise, No, repeat NO, nada, none, zip, zero, zilcho problems with my cooling system. There are no flaws or damage that can be attributed to Dex-cool either directly or indirectly. If not mixed with anything other than pure water, and used in a properly maintained system, Dex-cool will treat you as well as it has me. I'm not trying to push anything here. What can I say? I either did everything right, or got lucky. It seems par for the course for me. I've had a very good overall time with my j-body. I've heard so much negative publicity of these cars, that I've come to think I have an 'anti-lemon' car. A Chitty-chitty-bang-bang, Herbie type of car.
Dex-Cool is in my car.. and it's got over 250,000kms (about 160,000 miles).
It's been put in there since day one. I've had the LIM gasket replaced, but that isn't due to Dex-Cool. That's because the gasket would fail regardless.
I've had a leak in my 1998, and used potable water to get me to a service station, and then got pre-mixed Dex-Cool put in. It ended up lasting until I got my Grand Am.
I've heard worse stories from people that have put in Dex-Cool "compatible" fluid (undiluted), or regular Prestone into the system and didn't flush it properly. Then again, some people put molasses into their crank case.
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And now for something completely different... Click the Minister.
Its not the problem with the coolant products, They are put through over and over testing to Pass OEM requirements. Its like anything, If things arent maintained on preventive maintance, Failure to engine parts happen, Things never last forever, Ive had my 01 cavalier for 2yrs now, No major issues, Ive done the preventive maintance as required. Only things may fail due to not replacing a part right away in which leaves me with another part to fail as well.
Well Thats just my 2 cents.
Dexcool is fine as long as you have an aluminum block (and almost everything else like the ecotec) and are running an inline 4 engine like the ecotec.
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"The Blue Bullet"
Good to know. I didn't think that our j-body's had any problems with it. Just thought is was kind of good info. for others with dex-cool. Maybe I should have put this in the Off-topic? Sorry mods. Thanks for all the replies.
My '99 Z had it in it for 99k miles before I sold it and it's still running. Some people have problems with DexCool because they don't know you can't mix it with non DexCool. It causes big problems.
Rob
Sold 2/2/05
81,000 miles with dex cool, thermostat just went but that I doubt would be related to the dexcool, Now my moms blazer wether it was due to dex cool or not had a lot of rust, wiped out 2 water pumps within 100,000 miles plugged the heater core and was just very nasty in general.
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2009 Ford Mustang V6
never had any problems with dex-cool
Ryan1
protomec wrote:
The only thing that really a potential issue on the J's is the water pump, which 2.4s are real notorious for failing regularly.
Don't forget about the 2.4 plastic water neck.
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I have yet to see one be removed with crumbling around the seal.
- 93 mph in the 1/8 mile
Member of J-Body Of Michigan.
Ive used regular coolant ever since the first time i flushed the radiator at about 25,xxx. I havent had a problem with ither coolants but I only ran dexcool for 25,xxx so I cant really tell. But I can tell you my 96 z24 still has the stock water pump and im at 149,xxx miles now. - Danny