Tow rating is a calculated value and varies based on the frame strength, axle strength, braking capability, number of tires and their load capacity at the rear axle. Any engineer can add 1,000 lbs with the knowledge that the safety margin may be reduced by 10% but if it helps marketing then who really cares?
What does matter to me is the overall performance when towing and the GM grade control and the GM exhaust brake setup is better than what one gets with a Ram or Ford pickup.
What I found interesting was the difference in tow rating and payload rating for the two very different F-450 trucks, standard pickup and chassis cab. Similar difference between Duramax 2500 and 3500 trucks with the latter gaining 6,000 lbs thanks to its being available with DRW.
What may not be readily apparent but the increases in GCWR over the past several years have pushed 1-ton pickups into the class where the driver needs a commercial driver license. I would also bet that it has pushed up insurance rates and DMV fees.
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