Originally Posted by
1BadAction
The fan in the 06 and 07s can be made to come in earlier than they do stock, I think since yours is a true mechanical fan, you're stuck with how they work. Something that would help, is throwing the biggest trans cooler you can fit on there and bypass the one in the radiator. That will take a good bit of cooling load of the rad. Either way, unless you find some special E-fan, I don't think it'll do what you want it to.
GM put mechanical fans on these because they wanted that 6500lb tow rating, and E-fans couldn't cut the mustard on their grade test.