Then, after the trailer is attached, adjust the weight-distributing springs so that the front returns to about the original height. Cross the safety chains under the tongue of the trailer so that the tongue won't drop to the road if the trailer should become separated from the hitch. Always leave enough slack in the chains so you can corner without the chains impeding the movement of the trailer. Do not allow the safety chains to drag on the ground. And don't forget the back half of this combo.
Many owners forget to check the trailer's brakes, electrical connections and tires.
If a trailer has been sitting for a long time, the tires can rot or split. See the GMC Trailering Guide for details. Represents minimum recommended hitches. Please refer to your trailer's User's Manual or ask your GMC sales professional.