2007 GMC Sierra 1500 Pickup Owner's Manual - Page 449

Weight-Distributing Hitches and Weight Carrying Hitches If you use a step-bumper hitch, the bumper could be damaged in sharp turns. Make sure there is ample room when turning to avoid contact between the trailer and the bumper. If you will be pulling a trailer that, when loaded, will weigh more than 5,000 lbs (2 270 kg) be sure to use a properly mounted weight-distributing hitch and sway control of the proper size. This equipment is very important for proper vehicle loading and good handling when driving. Always use a sway control if the trailer will weigh more than these limits. You can ask a hitch dealer about sway controls. Fifth Wheel and Gooseneck Trailering A: Body to Ground Distance B: Front of Vehicle When using a weight-distributing hitch, the hitch must be adjusted so the distance (A) remains the same both before and after coupling the trailer to the tow vehicle. Fifth wheel and gooseneck trailers can be used with many pickup models. These trailers place a larger percentage of the weight (kingpin weight) on the tow vehicle than conventional trailers. Make sure this weight does not cause the vehicle to exceed GAWR or GVWR. Fifth wheel or gooseneck kingpin weight should be 15 to 25 percent of the trailer weight up to the maximum amount specified in the trailering chart for your vehicle. See "Weight of the Trailer" in this section for more information. 449