Best Coolant For 2007 Silverado 4.8l?

[tcr1016]

Is the green stuff good over Dexcool, since I will be changing the coolant every year?? I have heard many bad things about Dexcool, even in new cars less than a year old. I need to change my coolant in my 2007 4.8L, which will be flushed with the thermostat removed.

[txab]

Stay with the Dex. Nothing wrong with it.

 

Why are you changing annually? That's overkill IMHO.

[Silverado4x4]

Death Cool with no air.

 

 

Huh.

[MS3DALE]

Stay with the Dex. Nothing wrong with it.

 

Why are you changing annually? That's overkill IMHO.

 

Agreed,and agreed....stay with Dex-Cool,and changing it every year is a waste of time and money,I mean you can if you want,and it certainly wouldn't hurt a thing,but I wouldn't change it for at least a few years.

[CapitalTruck]

"It certainly wouldn't hurt." Well, that might not be entirely true. Dex-Cool was designed for longer service intervals, should probably be used for such. (I change mine every 2-3 years or 75k)

 

Here is some info from Motor Magazine August 2010:

 

"OAT [Organic Acid Technology, i.e. Dex-Cool]antifreezes last a long time, but also take a long time—about 5000 miles—to establish protection for cooling system passages. And the slow action means they can’t quickly protect water pumps that are pockmarked by cavitation. So the pump and cooling system must be engineered to minimize cavitation, which is primarily a high-load issue. The chemical 2-EHA causes leaks in silicone rubber gaskets and Nylon 66 gasket carriers, so they must be avoided."

 

"Because OAT antifreezes protect best when the system is absolutely full, which means the coolant is in contact with the walls of the system, maintaining a full fill becomes another issue. This is particularly important with cast-iron engine blocks, where a low level causes rust “blushing” on cooling system walls, a pickup of the rust from coolant flow and deposits in the radiator (see the photo on page 26)."