Will 285 65R18's fit a 08 Silverado 2500?
 

Recently I've been looking for a set of wheels and tires for my 08 Silverado 2500HD. I've found a set of 18x8.5 Eagle Alloy Series 114 wheels that I like, now I need a set of tires that will fit. I was at the wheel dealer to look at the wheels and a set of 285 65R16 Hankook tires, but he was not willing to take a wheel off to make sure the clearance was good. It looks like it will be very close to the inner fender and my stock chevy mud flaps. Any one have a combo similar to this? Other suggestions?

P.S. I'm not into lift kits or cutting up a new truck!