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I’ve heard arguments against using Dexcool in my 2004 Suburban. It is supposedly corrosive once it starts breaking down. Any opinions?

Imo without commenting on a brand, If it’s recommended by the manufacturer, there should be no problems. I would inquire with service rep on this brand if you have concerns. Long life’s are touted to last longer, I still change them more often then recommended.

It is supposedly corrosive once it starts breaking down

And why would you allow it to start breaking down. Like daqosa I recommend changing it at least as often as recommended. With Dexcool I would likely change it a bit more often. Alwas check with GM to see what they are currently recommending.

Here’s a good article on Dexcool. The most important point was to change the radiator cap to a Stant Model 10230 or 11230. Read the article for the explanation. Sludging occurs when air get into the cooling system from a contaminated radiator. cap.

The intake gasket on my 2000 Blazer was replaced at ~44k miles (Feb 200) right after the Dexcool was changed. There was no sludging in the cooling system at the time. I switched over to the Green antifreeze after the gasket was replaced. I change the coolant every 3 years and have had no further problems.

I used Dexcool in a 1995 Dodge Dakota for 6 years with no problems. If you haven’t had any problems to date stay with the Dexcool.

Ed B.

I had the same question for my mechanic a few years ago.

If I recall, according to him, the supposed corrosive effect of Dex Cool (aka “Death Cool”) had more to do with poorly designed head gaskets on several GM vehicles than the antifreeze itself. It didn’t matter how old or fresh the antifreeze was, if you had such a vehicle, the fluid would eat away at your head gasket regardless.

For all other vehicles, the Dex Cool has a very long lifespan. Isn’t the recommend schedule for changing the fluid something like 150,000 miles?

I’ve seen the distruction that can be caused when a cooling system is neglected with Dexcool. And it’s caused when air gets entrained in the cooling system. This causes the Dexcool to become acidic where it corrodes anything it comes in contact with.

The misconception with Dexcool is people think it can go 5 years/150,000 miles without a problem. Not true! Texaco never made that claim with Dexcool. Their claim was Dexcool COULD go 5 years/150,000 miles. They never claimed it WOULD go 5 years/150,000 miles.

Big difference!


All I can tell you that if you use DEXCOOL, don’t mix it with anything else! and make sure the cooling system is squeaky clean before you put it in.