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Fifth Wheel CouplingKingpin Coupling

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Modding since 2024

API Referencevecontrollercouplings

Fifth Wheel Coupling

Controls the fifth wheel coupling mechanism on tractor units. Manages the locking jaw that secures the trailer kingpin, detecting connection state and providing lock/unlock functionality.

Controls the fifth wheel coupling mechanism on tractor units. Manages the locking jaw that secures the trailer kingpin, detecting connection state and providing lock/unlock functionality.


Public API

FunctionDescription
detachFifthwheel()Manually triggers the decoupling of the current trailer.
setFifthwheelIndicatorVisibility(visible)Toggles visual indicators for the tractor's coupling point and requests nearby trailers to show their kingpins.
module.initSounds(jbeamData)Initializes sound resources.
module.onCouplerFound(nodeId, obj2id, obj2nodeId)print("found")
module.isAttached()Checks if attached.
module.toggleFifthwheelIndicatorVisibility()Toggles fifthwheel indicator visibility.

Hooks

HookDescription
init(jbeamData)Identifies the coupling node and physical properties (radius, strength) from JBeam.
updateGFX(dt)Polls nearby vehicles for compatible kingpins and manages the multi-stage state machine (detached, attaching, attached, detaching).
onCouplerAttached(nodeId, obj2id, obj2nodeId, attachForce)Callback when a physical connection is made. Triggers sounds and updates status electrics.
onCouplerDetached(nodeId, obj2id, obj2nodeId, breakForce)Callback when the connection is severed.
module.reset(jbeamData)Resets the controller to its initial state.

See Also

  • Kingpin — Trailer-side kingpin controller
  • Advanced Coupler Control — Automated coupling logic

Transbrake

Controls a transmission-based launch device that locks the output shaft by simultaneously engaging forward and reverse gears. Used in drag racing to hold the vehicle stationary against full engine power, enabling maximum-effort launches when released.

Kingpin Coupling

Controls the kingpin assembly on the trailer side of a fifth-wheel coupling. Manages the coupling interface that mates with the tractor's fifth wheel plate.

On this page

Public APIHooksSee Also