2003 GMC Envoy Owner's Manual - Page 285

Towing a Trailer To identify the trailering capacity of your vehicle, you should read the information in "Weight of the Trailer" that appears later in this section. Trailering is different than just driving your vehicle by itself. Trailering means changes in handling, durability and fuel economy. Successful, safe trailering takes correct equipment, and it has to be used properly. That's the reason for this part. In it are many time-tested, important trailering tips and safety rules. Many of these are important for your safety and that of your passengers. So please read this section carefully before you pull a trailer. If you don't use the correct eql , ment and drive properly, you can lose control when you pull a trailer. For example, if the trailer is too heavy, the brakes may not work well -- or even at all. You and your passengers could be seriously injured. Pull a trailer only if you have followed all the steps in this section. Ask your dealer for advice and information about towing a trailer with your vehicle. Notice: Pulling a trailer improperly can damage your vehicle and result in costly repairs not covered by your warranty. To pull a trailer correctly, follow the advice in this part, and see your dealer for important information about towing a trailer with your vehicle. Additional rear axle maintenance is required for a vehicle used to tow a trailer. See "Scheduled Maintenance Services" in the Index. 4-52