I have heard form different sources that DexCool colant may be harmful for engines. Does anybody know which coolant is better? Thanks

 

If the truck in your avitar is your truck in question, then the engine was designed for Dexcool. The only time you will have trouble with Dexcool is if oyu dont keep the overflow tank full, have a fualty radiator cap, or leave air in the system. Air is the reason for problems in the Dexcool systems. The solution is to keep the air out. Good for 150,000 miles or 6 years does not mean you do not have to maintain the cooling system.

 

Thank you very much for the answer. The overflow tank is always full and as far as i know there is now any leak in the cooling system. I am not sure about about air in the system, but the engine runs smooth and has normal temperature. What do you mean when said to maintain the cooling system?

 

Maintenance is simple.
Keep teh overflow tank full, to the proper line.
Pop the radiator cap about once per month just so look see for any corrosion.

 

One also should note that Dexcool and green coolant should never be mixed. the reasom for this, or soI am told, is that one has a mineral lubricant in it and the other has a petroleum lubricant. When mixed, the two willreact andbe madeinto a highly corrosive chemical that, over time, will corrode the inside of the radiator and causewater pump failure.

 

I mixed dexcool and the all makes all models kind........they dont sell any small jugs of dexcool dammit!

 

also theres a ton of posts about this....and in short i think the "all makes all models" seems to be the best way to go.

 

I have found Prestone's Yellow All Makes, All Models Extended life coolant to be excellent.