Trailer Terms Index

GVWR: The Gross Vehicle Weight Rating is the maximum allowable gross weight of the trailer & its contents. The gross weight of the trailer includes the weight of the trailer & all of the items within it (such as cargo & other supplies).

GAWR: The Gross Axle Weight Rating is the maximum gross weight that an axle can support. It is the lowest of axle, wheel, or tire rating. Sometimes the tire or wheel rating is lower than the axle manufacturers rating, & will then determine GAWR. The sum total of the GAWR for all trailer axles may be less than the GVWR for the trailer, because some of the trailer load is carried by the tow vehicle, rather than by the trailer axle(s). The total weight of the cargo & trailer must not exceed the GVWR, & the load on an axle must not exceed its GAWR.

Tire Size: The tire size & load range for your trailer.

Rim Size: The rim size & load range for your trailer.

PSI: The tire air pressure (Kilopascals/Pounds per Square Inch) measured with tires cold.

VIN: The Vehicle Identification Number.

Vehicle Type: Model or style of trailer.

ST: An "ST" is an indication the tire is for trailer use only.

Max. Load Dual kg (lbs) at kPa (psi) Cold: This information indicates the maximum load & tire pressure when the tire is used as a dual, that is, when four tires are put on each rear axle (a total of six or more tires on the vehicle).

Max. Load Single kg (lbs) at kPa (psi) Cold: This information indicates the maximum load & tire pressure when the tire is used as a single.

Load Range: This information identifies the tire’s load-carrying capabilities & its inflation limits.

Gooseneck: Trailer that attaches to a ball in the bed of a pickup.

Bumper pull: Trailer that connects to a ball hitch that’s attached to the tow vehicle's frame or bumper. Also called "tag hitch" trailer.

5th Wheel: Trailer that attaches to a plate in a pickup.