Back to Truckers Glossary
Maintenance & Inspection Terms

Truck Maintenance & Inspection Glossary

Plain-English definitions for DVIRs, pre-trips, brakes, tires, lights, ABS, air leaks, out-of-service risks, roadside inspections, and common truck maintenance terms.

Searchable Terms

Maintenance Dictionary

Tap “Full meaning” to open a longer explanation without leaving the page.

DVIR

Driver Vehicle Inspection Report.

Pre-Trip Inspection

Inspection completed before driving.

Post-Trip Inspection

Inspection completed after a trip or shift.

ABS

Anti-lock Braking System.

Brake Chamber

Air-brake component that applies brake force.

Slack Adjuster

Brake component that helps maintain adjustment.

Pushrod Travel

Brake chamber rod movement during brake application.

Air Leak

Loss of air pressure from truck systems.

Low Air Warning

Alert for unsafe air-brake pressure.

Brake Lining

Friction material used for braking.

Tire Tread Depth

Remaining usable tread on a tire.

Sidewall Damage

Damage on the side of a tire.

Hub Oil

Oil that lubricates wheel-end components.

Wheel Seal Leak

Oil leak from the wheel-end seal.

Marker Light

Light showing vehicle outline and position.

Clearance Light

Light showing vehicle width or height.

Conspicuity Tape

Reflective tape used for visibility.

Coupling

Connecting tractor and trailer.

Tug Test

Pull test to confirm trailer is locked.

Out-of-Service

Vehicle or driver cannot operate until corrected.

Roadside Inspection

DOT inspection of driver, vehicle, or cargo.

Pigtail

Electrical cord between tractor and trailer.

Glad Hands

Air-line connectors between tractor and trailer.

Landing Gear

Trailer support legs used when disconnected.

Kingpin

Trailer pin that locks into the fifth wheel.

Fifth Wheel

Tractor coupling plate for the trailer kingpin.