Equipment / Trailer parts
Landing Gear in trucking
Plain-English explanation
Landing gear is the retractable support structure on the underside of the front of a trailer that keeps the trailer upright and stable when it is uncoupled from a tractor. When a driver drops a trailer, they lower the landing gear to support the trailer's weight; when they pick up a trailer, they raise the landing gear completely before pulling away. Landing gear is operated by a hand crank on the driver's side of the trailer. Most landing gear has two speed settings: - High gear (fast): for rapid height adjustment when the trailer is empty or lightly loaded - Low gear (slow, high torque): for lifting the full weight of a loaded trailer off the ground during coupling The shift between high and low gear is made by pulling out and turning the crank to engage the appropriate setting. Starting in low gear when the trailer is too heavy to lift in high gear prevents gear stripping; switching to high gear for final adjustment speeds up the process. During coupling, the driver adjusts landing gear height so the trailer's kingpin is at the right position for the tractor's fifth wheel plate. After coupling and confirming the fifth wheel is locked, the driver raises the landing gear fully. Driving with partially raised landing gear risks the gear catching the ground on a grade or sharp turn and bending the frame. Damaged or improperly retracted landing gear is one of the more common findings on pre-trip inspections and roadside checks.
Equipment terms are best read physically: what is on the tractor, what trailer is assigned, how the freight loads, and what the driver can inspect before rolling.
Why it matters in trucking
Landing gear is a basic but critical piece of operational equipment. A driver who does not fully crank up the landing gear before pulling away risks damage to the trailer frame and gear mechanism, which can result in an out-of-service condition, a road hazard, or a costly repair. Proper landing gear procedure is part of the standard coupling checklist.
The right equipment term helps prevent the wrong truck from being sent to pickup, especially for reefer, flatbed, liftgate, power-only, or drop-trailer work.
Example in real use
A driver picks up a loaded trailer at a distribution center. The trailer has been sitting on high landing gear. The driver backs under, sets the fifth wheel, and feels the click of the kingpin locking. They then switch the landing gear crank to low gear and crank to lift the trailer weight off the pads. Once the trailer is riding on the fifth wheel, they switch to high gear to quickly retract the gear legs to full up position. They complete the remaining coupling steps (air lines, lights check) before pulling away.
Where it shows up
Landing gear matters whenever a trailer is dropped, hooked, staged, or left loaded in a yard.
What to check first
- Firm, level ground before dropping.
- Legs lowered enough to support the trailer.
- Gear raised fully before leaving.
- Bent legs, missing handle, or hard cranking reported.
Common mistakes or confusion
- Pulling away with landing gear not fully retracted — even partially lowered gear can catch on curb cuts, grade changes, and dock edges, causing frame damage and a breakdown.
- Starting in high gear to crank a fully loaded trailer — high gear does not have enough torque to lift heavy loads and will strip gears; always start in low gear when the trailer is loaded.
- Not checking the landing gear pads during pre-trip — broken or missing pads change the trailer height and can cause coupling alignment problems.
Related terms
Related guides
Truck Parts and Equipment Terms is the best next place to keep learning this topic.
Sources and last updated
Last updated: 2026-05-09