Safety Watch – July 2009

Heavy load

Trailer overloading may harm both your load and the traffic around you.

The accident: A pickup truck was towing an overloaded trailer when it caused a multiple-vehicle accident, closing one road for several hours and sending four people to the hospital. The trailer, carrying a skid steer, weighed 9,220 pounds, well over the 3,700-pound weight limit of the trailer hitch. Police say the driver of the pickup lost control because of the combined weight of the trailer and the skid steer, and the trailer became unhitched.

The bottom line: Every trailer has a designed maximum weight capacity, says the Trailer Safety Industry Coalition. The maximum weight capacity is stated on the trailer and in the trailer manuals as the gross vehicle weight rating, or GVWR. The GVWR is printed on a label or placard, often referred to as the certification of VIN label, which is mounted on the left front side of the trailer, typically within 6 inches of the floor line, or near the coupler.

In practical terms, the GVWR is the most a trailer should ever weigh with all cargo loaded. Exceeding this capacity rating overloads the trailer and can lead to safety problems, including poor handling and control, reduced braking ability, increased stopping distances and premature wearing of suspension system components, including tires and brakes.

If you ever have a question about how much your fully loaded trailer weighs, you should take it to a vehicle scale and weigh it. Truck service areas, grain elevators and weigh stations are just a few of the locations where such scales can be found. If the amount of the cargo causes the trailer to exceed its GVWR, you should unload some of the cargo items to reduce the weight.

Cargo must be loaded evenly within the trailer, both side to side and front to back. For example, if a trailer weighs 5,000 pounds empty and has a GVWR of 10,000 pounds, 5,000 pounds of cargo can be added. However, if all 5,000 pounds were added to the right side of the trailer, or only to the front or only to the back of the trailer, it would not handle correctly and could cause an accident. The heaviest items should be placed near the floor and directly over or as close to the forward-most axles as practical.