Maintenance when Trailer Towing

The vehicle needs service more often when pulling a trailer. See Maintenance Schedule on page 11‑3. Things that are especially important in trailer operation are automatic transmission fluid, engine oil, axle lubricant, belts, cooling system, and brake system. It is a good idea to inspect these before and during the trip.

Check periodically to see that all hitch nuts and bolts are tight.

    See also:

    Brake Adjustment
    Every time the brakes are applied, with or without the vehicle moving, the brakes adjust for wear. ...

    Cooling System
    If the vehicle has the Duramax® Diesel engine, see the Duramax® Diesel Supplement for more information. The cooling system allows the engine to maintain the correct working temperature. 5.3 L En ...

    Automatic Door Locks
    The vehicle may have an automatic lock/unlock feature. This feature can be programmed using the Driver Information Center (DIC). See Vehicle Personalization (With DIC Buttons) on page 5‑52 for m ...