2009 Chevrolet Silverado 2500 HD Extended Cab Owner's Manual - Page 369

For example, adding a 700 lb (318 kg) snow plow actually adds more than 700 lbs (318 kg) to the front axle. Using the formula, if the snow plow is 4 ft (122 cm) in front of the front axle and the wheel base is 10 ft (305 cm), then: W = 700 lb (318 kg) A = 4 ft (122 cm) W.B. = 10 ft (305 cm) (W x (A + W.B.))/W.B. = (700 x (4 + 10))/10 = 980 lbs (445 kg) So, if your truck's front axle reserve capacity is more than 980 lbs (445 kg), you could add the snow plow without exceeding the front GAWR. 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 towards 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. { CAUTION: 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. Total vehicle reserve capacity is the difference between your GVWR and the weight of your truck with full fuel and passengers. It is the amount of weight you can add to your vehicle before reaching your GVWR. 4-41