Towing glossary
- GCWR (Gross Combined Weight Rating)
- GCWR is the maximum allowed weight of the loaded tow vehicle and the loaded trailer together, set by the manufacturer for a specific engine, axle ratio and drive configuration.
- GVWR (Gross Vehicle Weight Rating)
- GVWR is the maximum allowed weight of the tow vehicle itself when loaded, including passengers, cargo, fluids and the trailer's tongue weight pressing down on the hitch.
- Payload
- Payload is the weight a vehicle can carry in its cab and bed or cargo area, calculated as GVWR minus curb weight, and it includes the trailer's tongue weight.
- Tongue weight
- Tongue weight is the downward force a trailer's coupler applies to the hitch ball, normally 10–15% of the loaded trailer weight for a conventional trailer.
- Weight-distribution hitch (WDH)
- A weight-distribution hitch uses spring bars to move part of the tongue weight from the tow vehicle's rear axle to its front axle and the trailer axles.
- Hitch (receiver) class
- Receiver hitches are grouped into SAE J684 classes by maximum trailer weight: Class I up to 2,000 lb, Class II up to 3,500 lb, Class III up to 8,000 lb, Class IV up to 10,000 lb and Class V above 10,000 lb.
- SAE J2807
- SAE J2807 is the industry test standard for tow ratings, covering acceleration, grade launch, cooling on the Davis Dam grade and handling with a defined trailer.
- Curb weight
- Curb weight is the weight of the vehicle with all standard equipment and a full tank of fuel but no passengers or cargo.