Originally Posted by deiselpower
I am rigging up a 350 SBC (aluminum heads and intake) for a buddy and he wants to put in some Dexcool coolant from Halvoline, I heard of some horror stories with the newer Ls engines. Should we get rid of the dexcool and get some good old green stuff? Thanks
The horror stories about this stuff are real. Works well when it works, but the slightest entry of air into the cooling system sets off a colossal chain of destructive events. This is made for people who buy cars like they buy toasters, purchase and use for a hundred thousand miles without ever peaking inside. For tinkerers that will undoubtedly drain and refill the cooling system for modifications to the engine or maintenance on the cooling system, Dexcool just isn't the stuff to use as once it's contaminated it turns to thick corrosive gunk. Go with Prestone (Ethylene glycol, poisonous) or Sierra (Propylene Glycol, not so poisonous). Or with Evans for a waterless antifreeze/coolant.
Use only distilled water to dilute the water mix antifreezes. Tap water is highly destructive to aluminum engine parts it contacts.