Home » Training » Trailer Glossary Trailer Glossary Does trailer terminology have you confused? No problem! The Trailer Technician Trailer Glossary provides the definitions of commonly used terminology from the heavy-duty truck and semi-trailer industry. # 7-Way A A-TrainABS EventABS Indicator LampAero SkirtsAir BagAir Brake SystemAir DryerAir LinesAir ReservoirAir Ride SuspensionAir SpringAir TankAmerican Wire Gauge (AWG)Annual InspectionAnti-Lock Braking System (ABS)Apitong FlooringAxle B B-TrainBlind RivetBlink CodesBobtailBogieBolster PlateBolster Plate HeightBottom RailBrake ActuatorBrake ChamberBrake ControllerBrake DragBrake DrumBrake FadeBrake ForceBrake Monitoring System (BMS)Brake StrokeBridge FormulaBrinell HardnessBuck RivetBulkheadBullet ConnectorButt Connector C C-TrainCamberCAT ScalesCenter-of-GravityChassis, ContainerClass 1 TruckClass 2 TruckClass 3 TruckClass 4 TruckClass 5 TruckClass 6 TruckClass 7 TruckClass 8 TruckClearance LightsClevisCommercial Driver’s License (CDL)Commercial Motor Vehicles (CMVs)Commercial Vehicle Safety Plan (CVSP)Commercial TrailerCompliance, Safety, Accountability Program (CSA)ConestogaConspicuity Tape (DOT Tape, Reflective Tape)ContainerContinuity TesterCorner RadiusCrash PlateCrossmemberCurbsideCushion Foot D Dead AxleDepartment of Transportation (DOT)Desiccant CartridgeDiagnostic Trouble Code (DTC)Dielectric GreaseDiesel Particulate Filter (DPF)Disc BrakesDock LevelerDock LockDock WalkDollyDolly LegsDoor Hold BackDoor SealDoor, OverheadDoor, SwingDoublesDrawbar EyeDrayageDriver Vehicle Inspection Report (DVIR)Drop and HookDrop Deck TrailerDrum BrakeDry Van TrailerDuraPlate®Dust ShieldDuty CycleDuty Rating (Ladder) E Electronic Braking Systems (EBS)Electronic Control Unit (ECU)Electronic Logging Device (ELD)Electronic Stability Control (ESC)Emergency Air Line (Red)End PlayExtendable Double Drop TrailerExtendable Flatbed Trailer F Federal Motor Vehicle Safety Standards (FMVSS)Fiberglass Reinforced Composite (FRC)Fiberglass Reinforced Plastics (FRP)Fifth WheelFifth Wheel HeightFifth Wheel Top PlateFixed TandemFlapsFlash CodeFlat RateFlat SpottingFlatbed TrailerFloat TrailerFloor, CompositeFloor, LaminatedFloor, ShiplapFloor, Tongue & GrooveFoundation Brake System G Galvanic CorrosionGalvanizedGeofencingGladhandGooseneck TrailerGross Axle Weight Rating (GAWR)Gross Combination Weight (GCW)Gross Vehicle Weight (GVW)Gross Vehicle Weight Rating (GVWR)Ground Bearing H Harness, WiringHeavy Duty TruckHigh Base RailHours of Service (HOS)HubodometerHydrogenated Nitrile Butadiene Rubber (HNBR) I ICC BumperIntermodal J JackknifeJohnson BarJounce K Keruing FlooringKingpinKingpin LockKingpin Plate L Landing GearLash RingLeaf Spring SuspensionLess-Than-Truckload (LTL)Lift AxleLift GateLoad BarLoad ConcentrationLoad LockLogistic SeamsLogistic TrackLong StrokeLonger Combination Vehicle (LCV)Lowboy TrailerLumen M Marker LightsMROMulti Meter N Nitrile Butadiene Rubber (NBR)Non-Ground BearingNoseNose BoxNose Cone O Off-RoadOhmOn-RoadOriginal Equipment Manufacturer (OEM)Out of Service (OOS)OutriggerOverhang P PalletPayload CapacityPDI InspectionPick-up and Delivery (P&D)PiggybackPigtailPintle HookPlacardPlatooningPop RivetPounds Per Square Inch (PSI)Pre-Trip InspectionPredictive Maintenance (PdM)Preventive Maintenance (PM)PupPush RodPush Rod Length Q Quick Release Valve R Rear Impact Guard (RIG)ReboundRed TagRefrigerated Trailer (Reefer)RelayRemovable Gooseneck Trailer (RNG)Ride HeightRigid Fifth WheelRoadRailer TrailerRoadsideRocky Mountain DoublesRoll AxisRoll CenterRotorRub Rail S SAE J560SAE J1939SAE J2228Safety Measurement System (SMS)Sand ShoeS-CamScuff LinerSemi-TrailerService Line (Blue)Service BrakeSheet & PostShort StrokeSide RailSide SkirtsSlide TrackSliding TandemSidekit TrailerSlack AdjusterSlide TravelSliding Fifth WheelSliding TandemSmart TrailerSolid RivetSpecialty TrailerSpindleSpread AxleSpring Brake ChamberStandard Repair Time (SRT)Static Load Radius (SLR)Stationary Fifth WheelStep Deck TrailerStretch RGN TrailerStretch Single Drop Deck TrailerSuper SingleSupply LineSuspension T Tack WeldTandemTankerTare WeightTautlinerTelematicsTerminal TractorThermal EventTire Inflation System (TIS)Tire Load RatingTire Pressure Monitoring System (TPMS)Tire Rolling RadiusTone RingTop RailTorque BalanceTowed Vehicle Weight (TVW)TrackTractorTractor TrailerTrailer DropTrailer On Flat Car (TOFC)Trailer PushTrailer TechnicianTrailer WalkTransportation Management System (TMS)Tread DepthTreadle ValveTri-axleTriplesTruckload (TL)Turnpike Doubles U Upper Coupler V Van TrailerVehicle Identification Number (VIN)Vehicle Maintenance Reporting Standards (VMRS)VIN TagVertical Load CapacityVolt W WattWeigh StationWheel BaseWheel EndWheel Speed SensorWheel Torque X Y Yard CheckYard JockeyYard Management System (YMS)Yard TractorYoke Z Click to share on Facebook (Opens in new window)Click to share on X (Opens in new window)Click to share on Reddit (Opens in new window)Click to share on Pinterest (Opens in new window)Click to share on LinkedIn (Opens in new window)