By Aaron Lindstrom, EnterpriseFleet Management
In today’s high performance driven economy, businesses want more from their fleet of vehicles: improved performance, lower maintenance, longer life and greater fuel economy – and reduced life-cycle costs. In addition, because modern vehicles are increasingly complex and technologically advanced, all the parts, though manufactured by many suppliers, must work together as a complementary system for optimum performance.
Spec’ing vehicles based on accurate information can make a big difference in selecting components that will provide maximum performance, lowest service and repair costs, and best resale value over the life of the vehicle.
One of the most critical considerations is the gross vehicle weight rating (GVWR). Simply put, the GVWR refers to the maximum a vehicle can weigh at any time. The GVWR includes the net weight of the vehicle, plus the weight of the driver and any passengers, as well as fuel, cargo and any aftermarket equipment or accessories added to the vehicle.
Exceeding the GVWR by regularly overloading a vehicle not only reduces its service life significantly, it also can be a safety hazard. It could also expose a company to legal litigation and judgments if there is an accident and the facts show that it was caused by an overweight vehicle.
Manufacturers determine the maximum acceptable weight limits for each vehicle by considering the combined weight of the strongest weight bearing components (the axles) and the weaker components (vehicle body, frame, suspension, and tires). When these are factored in, the manufacturer sets the vehicle’s GVWR in accordance with established industry standards. However, modifying the chassis by adding helper springs or heavier tires/components does not increase the GVWR or payload capacity.
The easiest way to figure out how much weight a vehicle is designed to carry is to subtract its net weight (found in your owner’s manual) from the GVR (usually on a placard on the door jam). The remaining number is the maximum weight the vehicle can safely carry, including the driver, fuel and cargo. Aftermarket accessories and equipment also increases the weight of the vehicle and must be added to the net weight listed in the owner’s manual. The best way to check the net weight is to take the vehicle to a certified scale and weigh it.
While drivers may continue to load materials into their trucks if there appears to be space left in the vehicle, the frame, suspension, brakes and tires are not designed for weights above the rating the manufacturer has established. Overloading a truck can cause premature mechanical failures on driveline components such as axles, drive shaft universal joints, transmission, and suspension parts and brakes. In addition, vehicles that operate above the GVWR are a potential safety hazard by affecting the way the truck handles and stops.
A good rule of thumb to follow is what most people in the trucking industry refer to as the “80 percent rule.” While your truck will certainly be loaded to 100 percent capacity from time to time, the best practice is to generally spec your vehicle to operate at 80 percent of its GVWR. This will reduce the operating costs of your truck and help extend its service life.
Although years ago, overloading a vehicle was more commonplace, times have changed. While today’s manufacturer’s warranties usually cover everything except normal wear-and-tear items like tires, brake pads and filters, failure to comply with the truck’s GVWR can often end up voiding the warranty.
Spec’ing new vehicles should always begin with a detailed assessment of a company’s needs, including annual mileage, payload requirement and service application. The initial cost of a properly spec’d vehicle may be slightly higher then expected, but you will save money in the long run with less expensive maintenance and repairs, reduced down time, and higher resale value.