Trailer Running Gear Glossary
Arm Lengths
The length of the Torflex torsion arm as measured from the axis of the axle tube to the axis of the spindle.
Axle Capacity
The beam capacity of the axle model selected. This value may be derated based on the hub face and spring center or outside bracket dimensions, if the recommended dimensions are exceeded. (See G.A.W.R. for other rating information.)
Axle Combination
The number of axles to be used in your application (single, tandem, triple).
Axle Suspension
A system which provides a method for absorbing shock as well as attachment of axles to a vehicle frame.
Backing Plate
The circular, plate-shaped brake component, bolted to the brake flange or directly welded to the axle, to which all other brake components are attached.
Bracket Dimension
The dimension from the outside of one mounting bracket to the outside of the other mounting bracket.
Brake Actuation
The method by which a brake is energized. Air, Electric, Electric / Hydraulic, and Hydraulic Surge are available on most axle models.
Brake Flange
A mounting plate, attached to either the axle or the spindle, to which the brake assembly is bolted.
Brake Magnet
An electromagnet within the brake assembly that when actuated initiates the braking action.
Breakaway System
A system that engages brakes in the event of a separation of the trailer from the tow vehicle.
Camber
The angular relationship of the wheel to the road surface in the vertical plane. Axles are typically built with a pre-determined bend in the tube that compensates for the expected deflection under load.
Derate
When an axle is built to exceed the recommended overhang dimensions, the rated capacity will be diminished. (See G.A.W.R. for other rating information.)
Double Eye
Leaf springs with eyes formed in each end of the spring.
Drop Height
The distance from the center of the spindle (center of the tire) to the center of the axle tube.
Drop Spindle
A forged spindle with a cross-section that allows the axle tube to be offset from the axis of the wheel. Used for applications which require lower frame and deck heights. Some models offer a choice of drop heights.
Electric Brake
A mechanical braking system used in conjunction with drum brakes that actuates the stopping mechanism with electromagnets and levers. The electrical source is supplied from the tow vehicle by an electronic brake controller.
Equalizer
A suspension component that allows transfer of a portion of the load on one axle to the adjacent axle(s) when traversing an uneven surface.
E-Z Lube Feature
A bearing lubrication system that consists of a grease fitting installed into the end of each spindle. A channel is provided to distribute grease to the inner bearing. A special double lip seal diverts the lubricant back toward the outboard bearing, thus lubricating both bearings without hub removal.
Gross Axle Weight Rating (GAWR)
The rated capacity of the vehicle running gear as defined by the lowest rated component in the system. Those components considered are the axle beam, the suspension system, the wheels or rims and the tires.