Basic Trailer Wiring

All regular, extended cab and crew cab pickups have a seven-wire trailer towing harness.

For vehicles not equipped with heavy duty trailering, the harness is secured to the vehicle's frame behind the spare tire mount. The harness requires the installation of a trailer connector, which is available through your dealer.

If towing a light-duty trailer with a standard four-way round pin connector, an adapter is available from your dealer.

    See also:

    Federal Communications Commission (FCC) Rules and with Industry Canada Standards
    See Radio Frequency Statement on page 13‑21 for information regarding Part 15 of the Federal Communications Commission (FCC) Rules and with Industry Canada Standards RSS-GEN/210/220/310. ...

    Cellular and GPS Antennas
    Avoid placing items over or near the antenna to prevent blocking cellular and GPS signal reception. Cellular reception is required for OnStar to send remote signals to the vehicle. ...

    What to Use
    To determine what kind of fluid to use, see Recommended Fluids and Lubricants on page 11‑12. Always use the proper fluid. Notice: Use of the incorrect fluid may damage the vehicle and the damag ...