i run this in my cummins and it cools a hell of alot better then the purple stuff. May cost a little more but i think its worth it

http://www.amsoil.com/storefront/ant.aspx

 

There is a place called Zoro Tools (www.zorotools.com) that sells Zerex G-05 for $15.19 and if you buy $50.00 worth it has free shipping. They are fast and reliable. This is not a premixed antifreeze so you have to buy a few gallons of Distilled Water. Good stuff
Antifreeze, G05, Container Size 1 Gal, Size/Net Weight 1 Gal, Yellow, Bottle, Yellow, 8 pH, Boiling Point 226 F, Freezing Point -34 F, Flash Point 250 F, 1.1375 Specific Gravity, For Use With Chrysler, Ford, Mercedes, Deere, and GM, Check Specific Model, ASTM, SAE
Specific Gravity : 1.1375
Hoat