Not sure about the 07 engine, but I had a 2002 GMC 1500HD with a 6.0, and it was a beast! It had a tune by Wait4Me, a cold air intake, and true duals. I pulled a 28' fifth wheel RV all summer and a 24' enclosed snowmobile trailer all winter, and never had a problem keeping up with my diesel buddies, much to their chagrin.
