2010 Mercedes GLK-Class Owner's Manual - Page 249

Driving instructions Vehicle and trailer weights and ratings The Gross Trailer Weight (GTW) is the weight of the trailer plus the weight of all cargo, equipment, luggage, etc. loaded on the trailer. The maximum permissible GTW to be towed: 3 500 lb (1 588 kg). Trailer Tongue Weight Rating (TWR) is the maximum permissible weight on the trailer tongue: 280 lb (127 kg) limit for MercedesBenz approved hitch receiver. Loading a trailer RWhen loading a trailer, you should observe that neither the permissible GTW, nor the Gross Vehicle Weight Rating (GVWR) are exceeded. The GVWR is indicated on the certification label located on the driver's door B-pillar (Y page 227). Maximum permissible values are listed on the safety compliance certification labels for the vehicle and for the trailer to be towed. The lowest value listed must be selected when determining how the vehicle and trailer are loaded. RThe tongue weight at the hitch ball must be 247 passengers and cargo, trailer fully loaded) weighed on a commercial scale. RCheck the vehicle's front and rear gross axle weight, the Gross Trailer Weight (GTW) and tongue weight. The values as measured must not exceed the weight limits listed under "Vehicle and trailer weights and ratings" (Y page 247). Observe maximum permitted trailer dimensions (width and length). Most states and all Canadian provinces require Rsafety chains between the towing vehicle and the trailer The chains should be criss-crossed under the trailer tongue. They must be attached to the hitch receiver, and not to the vehicle's bumper or axle. Make sure to leave enough slack in the chains to permit turning corners. separate brake system at various trailer weights break-away switch on trailers with a separate brake system. Check with your local state laws for specific requirements. The switch activates the trailer brakes in the possible event that the trailer might separate from the tow vehicle. Ra Ra added to the rear axle weight to prevent exceeding the rear Gross Axle Weight Rating (GAWR). The GAWR is indicated on the certification label located on the driver's door B-pillar (Y page 227). i Mercedes-Benz recommends loading the trailer in such a manner that it has a tongue weight between 8 % and 10 % of the GTW. i The weight of other accessories, passengers and cargo will reduce the maximum trailer weight and tongue weight your vehicle can tow. Checking weights of vehicle and trailer RTo assure that the towing vehicle and trailer are in compliance with the maximum permissible weight limits, have the loaded rig (towing vehicle including driver, ! Do not connect a trailer brake system (if trailer is so equipped) directly to the vehicle's hydraulic brake system, as your vehicle is equipped with antilock brakes. If you do, neither the vehicle's brakes nor the trailer's brakes will function properly. i The provided vehicle electrical wiring harness for trailer towing has a brake signal wire for hook-up to a brake controller. Z Operation Coupling a trailer