I'm still on the original Coolant, but think it's time for a change.
Should I take it to a dealer or mechanic and let them "flush" the system or
Can I drain the radiator myself and add new coolant.
Since I'm still under the 100,000 warranty, should I stick with Dexcool?
I've heard good things about the Peak "World" lifetime coolant.

Dunno, but an answer would help me too. As I'm at 92K and don't know the age.

Because I do not know, I would put the OEM stuff in again (or its equivalent).

I have heard that the OEM Dexcool stuff is overpriced crap and we should go with the traditional green ethylene glycol stuff.

I have heard reports that other stuff is the best thing since sliced bread.

I do know that diesel engines have historically had problems where the coolant was mis-behaving with catastrophic results. Something like the harsh fuel detonation causes coolant to cavitate and etch pinholes through cylinder walls. This was minimized (or eliminated) by using certain coolant additives.

So.... If anyone can give some solid information about this, including the official GM line, that would sure help.

In the absence of information I'd put the OEM coolant in. I don’t think GM would recommend a product that would ruin engines and make themselves liable for engine replacement.

I've been told that mixing green and dexcool is bad too. Turns to "jelly". A complete flush has to be preformed to remove it so I've heard. :dunno:

Bump....

????

pull up my post on dexcool. you'll probably find it if you use the search word "fleetguard".