Cirrus8

Several years ago, I changed my anti-freeze and used Prestone instead of Dex-cool. I did all the necessary burping but my Vette's normal operating temp went from 192* to 198*. So I am wondering, is Dex-cool a more efficient heat remover than Prestone? Is there a difference in surface tension (is the Dex-cool a "wetter" liquid? The Prestone is compatible with Dex-cool. Anyone have an opinion on this?

thisMSGgood4me

If the Prestone product you used was Dex-Cool Extended Life and not one of Prestone's other products, then you did in fact put Dex-Cool in your radiator. From the Prestone website: Prestone® Dex-Cool® Approved Antifreeze/Coolant has been approved by General Motors to be licensed as a DEX-COOL(r) product under the GM 6277M specification.

Vetteman Jack

Are you sure that the radiator area is free of debris - if not that could cause a rise in operating temp.

momo20

our vette's as well as the F-bodies are what they call bottom feeders. meaning the use air that comes in from the bottom of the car to help cool the rad and so forth...one draw back is that weeds, lil rocks and so forth get trapped in between the ac cond, and rad and limit the proper air flow...and don't say it does not happen on your car. I clean mine out at least once a month and I always have some sort of lil pile of stuff to sweep up after the fact

Cybermind

Something else you should look at is the concentration. What concentration of Dexcool and water did you use? Ideally 50/50 gives you the most efficient cooling while maintaining the corrosion resistance properties of the coolant. The higher the coolant concentration, the less cooling efficiency. The lower the coolant concentration, the more cooling efficiency at the expense of corrosion resistance and water pump lubrication.