Good News! I have pulled my 7500lbs camper around now on 3 different trips going over 200 miles each. The results of a programmer, Cold Air Intake, and a new upgraded exhaust makes the Silverado 5.3L wake up quite a bit. I am very pleased the way my chevy pulls. I run the speed limit and set the cruise. She runs between 3000-4500 rpms which was exactly what was commented on my question. Mileage I got 8-11 mpgs which is what I expected pulling a thee and half ton camper. Next updates will be LT tires and air bag suspension before my next trip to Tennessee. Thanks for all the advice and informative answers.