2011 Chevrolet Express 1500 Cargo Owner's Manual - Page 268
2011 Chevrolet Express 1500 Cargo Manual
Page 268 highlights
9-54 Driving and Operating Safety Chains Always attach chains between the vehicle and the trailer. Cross the safety chains under the tongue of the trailer to help prevent the tongue from contacting the road if it becomes separated from the hitch. Always leave just enough slack so the rig can turn. Never allow safety chains to drag on the ground. Will any holes need to be made in the body of the vehicle when a trailer hitch is installed? If using the wiring provided with the factory-installed trailering package, no holes need to be made in the body of the vehicle. However, if an aftermarket hitch is installed, holes may need to be made in the body. If holes are made in the body, then be sure to seal the holes later when the hitch is removed. If the holes are not sealed, deadly carbon monoxide (CO) from the engine's exhaust can get into the vehicle as well as dirt and water. See "Carbon Monoxide" under Engine Exhaust on page 9‑24. Trailer Wiring Harness The optional heavy-duty trailer wiring package includes a wiring harness, with a seven-pin connector at the rear of the vehicle and a four-wire harness assembly under the driver side of the instrument panel. The four-wire harness assembly comes without a connector. If the vehicle does not have a trailer hitch, the seven-wire harness assembly with connector is taped together and located in a frame pocket at the driver side rear left corner of the frame. If the vehicle has a trailer hitch, the seven-wire harness assembly with connector is attached to a bracket on the hitch platform. In both cases, the seven-wire harness has a connector and includes a 30-amp feed wire. Trailer Brakes A loaded trailer that weighs more than 680 kg (1,500 lbs) needs to have its own brake system that is adequate for the weight of the trailer. Be sure to read and follow the instructions for the trailer brakes so they are installed, adjusted and maintained properly.