2004 Chevrolet Silverado 1500 Pickup Owner's Manual - Page 356

In order to calculate the amount of weight any front accessory, such as a snow plow, is adding to the front axle, use the following formula: Where: W = Weight of added accessory A = Distance that the accessory is in front of the front axle W.B. = Vehicle Wheelbase For example, adding a 700 lb. (318 kg) snow plow actually adds more than 700 lb. (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 lb. (445 kg) (W x (A + W.B.)) /W.B.= Weight the accessory is adding to the front axle. So, if your truck's front axle reserve capacity is more than 980 lb. (445 kg), you could add the snow plow without exceeding the front GAWR. 4-66