2010 GMC Sierra 1500 Crew Cab Owner's Manual - Page 420

You can add heavier equipment on the front of the vehicle if you compensate for it by carrying fewer passengers, less cargo, or by positioning cargo toward the rear. This has the effect of reducing the load on the front. However, the front GAWR, rear GAWR, and the Gross Vehicle Weight Rating (GVWR) must never be exceeded. { WARNING: On some vehicles that have certain front mounted equipment, such as a snow plow, it may be possible to load the front axle to the front gross axle weight rating (GAWR) but not have enough weight on the rear axle to have proper braking performance. If your brakes can not work properly, you could have a crash. To help your brakes work properly when a snow plow is installed, always follow the snow plow manufacturer or installer's recommendation for rear ballast to ensure a proper front and rear weight distribution ratio, even though the actual front weight may be less than the front GAWR, and the total vehicle weight is less than the gross vehicle weight rating (GVWR). Maintaining a proper front and rear weight distribution ratio is necessary to provide proper braking performance. 5-44 Total vehicle reserve capacity is the difference between the GVWR and the weight of the truck with full fuel and passengers. It is the amount of weight that can be added to the vehicle before reaching the GVWR. Keep in mind that reserve capacity numbers are intended as a guide when selecting the amount of equipment or cargo the truck can carry. If unsure of the vehicle's front, rear, or total weight, go to a weigh station and weigh the vehicle. Your dealer can also help with this. The total vehicle reserve capacity for the vehicle can be found in the lower right corner of the Certification/Tire label as shown previously. See your dealer for additional advice and information about using a snow plow on the vehicle. Also, see Loading the Vehicle on page 5‑33.