Swapped thermostats in my neon this morning, the first cold snap made me notice the engine didn’t get as hot as it use to. I noticed the shelf in my garage has a jug of HOAT (Htbrid Organic Acid Technology) coolant for my Cummins Ram, Dex cool for stepdaughters cars, a jug of some red coolant that I have no clue what it’s for, and a couple of gallons of good old conventional green coolant.

My question: cars worked just fine for 90 plus years with good old ethylene glycol anti freeze, when and why did t this Mickey Mouse crap start with the different types of coolant? If it ain’t broke , why fix it?

The first type of special coolant I can recall is the dexcool crap in the early 90s. Was there something earlier?

 

At least two things contribute to the increasing array of anti-freeze sold.

• Each manufacturer tends to have their own formulation (which sometimes turns out badly, looking at you, GM)
• Much of the current proliferation is aimed at extending the life of the fill. I changed my Challenger to Mopar Parafull with 10 year/150,0000 mile rating. It's PN 68104496AA if you're interested for your Neon.

 

I think Dexcool gets a bad rap because of what it is added to and what is added to it. I have used it in all my fleet since it's appearance on the market and have never had a problem in any vehicle. I do make sure to thoroughly flush old coolant out.

 

Yes. Water (H2O). Times change, products change.

 

Be careful using the "long life" stuff. I thought I was doing a good thing by changing to that recently -- and promptly found I now had a leak in the radiator. I got it fixed at an old-time radiator shop (there are still a *few* around). The shop owner said to never use "long life" coolants; they have to be too strong initially in order to have that long life before they lose effectiveness. He said the best coolant currently is NAPA's green stuff (and distilled water). That's what I used when I put everything back together.
[Yes, my radiator was probably short on remaining life, but how much longer would it have gone if I hadn't switched products?]

 

Keep in mind yesterday's cooling system materials were vastly different than todays. When was the last time an OE used anything other than high temp plastic for radiator tanks? Have to go back to the '90's. Other than diesels, almost all engine blocks and cylinder heads are aluminum now rather than iron and many bolt on pieces (intakes, water pumps, etc.) are also high temp plastic. Not to mention seals and gaskets. Night and day differences between 'now' and 'then'. All that means is cooling system engineers have a new set of rules to work by for the coolant they design for new engines. Not surprising they can play around with much different formulations. May not necessarily amount to 'better' but definitely 'different'.

 

Make sure you don't use standard green coolant in a car that's designed for Dexcool. The only way to switch is to do it after an engine rebuild. Dexcool cars of the 90s and early 2000s have enough problems without trying to change the coolant.

 

Just as a general comment, last spring I was at the parts store and while waiting, IIRC, I counted 18 different coolants in stock, along the 20’ of shelf in front of me. I was dumbfounded! At the body shop, we pretty much always bought “OE” coolant from the dealers as part of the parts order unless what came out of the car clearly looked and smelled like “normal” old green coolant and the car was old enough to have had a coolant change done.