I have a 04 Z06, only 5,600 miles. I want to change out the original antifreeze. Which is the best brand to use? Thank you

 

Your original Dextron II has been in the car for the last 5 years, why not use it again?

 

I can, I wasn't sure if there is a newer, better antifreeze that my fellow vette owners use. Do I have to buy the Dextron II from a GM dealer or can I get it at an auto parts store? Thank you

 

I think he means DEXCOOL, not Dexron. Dexron II is an automatic transmission fluid.
The original Dexcool was made by Texaco Havoline, but I think they quit making it in the US so a lot of the local parts stores quit stocking it. Even Walmart used to have it, but now they only carry Prestone Dexcool. Prestone is now an official licensed GM manufacturer for Dexcool, so that is what I bought when I changed mine a few months ago.

Also, even though GM says the Dexcool can go 5 years without changing it, I never let mine go over 2 or 3 years. You still have freeze protection, but the corrosion inhibitors become depleted if you let it go too long.

You can buy pure Dexcool and dilute it with distilled water, or you can buy pre mixed Dexcool also at Walmart. The pre-mixed is a 50/50 mixture already diluted with water.

You can buy GM antifreeze at the dealer, but it will cost you $20 instead of $10, and it was probably manufactured by Prestone anyway.

 

In the last year I have changed the fluid in my 96, 01 and my sons 01Z. I had one gallon of the GM stuff for the balance I purchased prestone Dexcool (5year or 100K) fluid from my neighborhood Kragen. This was the second time to change my 01 coupe and the radiator was spotless, just perfect condition. My 01 only has 10K but the Dexcool preserved my radiator great so I used it again. And don't forget to use distilled water

 

Correct "Dexcool".

 

Dexcool, got it! Thank you guys so much!