Noobie question here. So I checked my coolant level today in my '01 Z28 and it appears the coolant is a little lower than the FILL COLD line on the dipstick by about a centimeter. I'm not sure which coolant was used in the car by the previous owner and I read that it was bad to mix coolants (example: mixing DEXCOOL and the universal green stuff). Is it alright if I just pour in a small amount of distilled water into the coolant reservoir to get it up to the recommended level? I don't want to pour in DEXCOOL just yet because I'm unsure which coolant is currently in the reservoir. Is there anyway to identify what kind of coolant I have in the vehicle?

Thanks in advance guys

 

Take the rad cap off (when it's cold of course) and look. Dexcool is orange and old-style is green.

Yes, adding water is good.

 

probably no way to id the coolant and be sure unless you are the original owner, you would be taking a chance. if there's no risk of freezing temperatures then yeah distilled water top off in the overflow tank would be fine. your other option is one of the "all makes/models" of antifreeze at the store which is close to a clear color if you had to add a significant amount of fluid like 1/2 gallon or more.

being a 2001 if you never had the coolant services now might be a good time... before you are forced to also service the radiator and heater core. using cheap all make/model antifreeze and just draining the radiator & refilling would be better than running on 10+ year old coolant. and if you go that far then pull your battery out so you can pull the coolant overflow reservoir out and rinse it out good with the hose.

 

I agree that you should drain all the old stuff out including the overflow reservoir, but I would not put in any radiator cleaners as you may end up with a bunch of leaks. That stuff is very corrosive .

 

Alright thanks everyone!! I will fill it up with water for the time being and I will flush the old stuff out as soon as I have the time to do so!