I've run Coopers on many trucks for over 15 years. I've had nothing but good luck with them. I'm currently running the STT tires in 315/75R16.
Well I have a 2" or 3" leveling kit and mine looks tall, but not that tall. Would you say you're about 4" over stock?It is a 2002 2500HD. It has the heavier plow coil springs up front, camper springs in the rear, and a Dana 80. Then I added a 2" front leveling kit, Timbren overloads in the rear, Moog trackbar. That's basically it.