Trailer Landing Gear Repair and Service

Landing gear is what holds a trailer up and level once it's uncoupled from the tractor, and it's cranked by hand at the start and end of nearly every trip. That much use, outdoors, under load, makes it a routine wear item — and a failure here can drop a loaded trailer or jam it where it sits.

The crank and gearbox

Turning the crank handle drives a gearbox that raises and lowers both legs together through a shaft connecting them. A crank that's hard to turn, that slips, or that turns without raising or lowering the legs points to the gearbox: worn or stripped gears, a sheared shaft or shear pin, or a gearbox that's low on or has lost its lubricant. A gearbox that's been run dry or has had water get into it wears faster from that point on, even after it's refilled.

Legs, pads and the shaft

Each leg telescopes to set the trailer's height and carries the load down through a foot or pad at the bottom. Check the legs for bending, especially after a trailer has been dropped off-level or on soft or uneven ground, and check that both legs raise and lower together — a leg that's lagging or binding means the connecting shaft, its couplers, or one leg's own mechanism has a problem. The foot or pad should sit flat and intact; a worn, bent or missing pad lets a leg sink or tip on soft ground.

Lubrication and wear points

Landing gear has several points that need regular lubrication to keep moving freely: the gearbox itself, the leg's internal shaft and outer tube, and the pivot points where the gear mounts to the trailer frame. A gear that's gone without lubrication for a long stretch, or that's been exposed to road salt and grit without being cleaned, is more likely to show the crank problems and binding described above. The landing gear manufacturer's documentation gives the lubricant type and the points to service for that model.

When to repair versus replace

A bent leg, a stripped gearbox, or a mounting bracket that's cracked or torn from the frame are usually a repair or replacement job rather than something to lubricate past. Because landing gear carries the trailer's full weight when parked, don't put a trailer back into service on gear that doesn't raise, lower and lock the way the manufacturer's documentation describes for that model.

What should the service record show?

A record of trailer landing gear service should show:

• what the customer reported: hard cranking, slipping, a leg lagging, a damaged pad;
• the gearbox, legs, shaft and pads as found;
• the lubrication points serviced and the lubricant used;
• what was repaired or replaced, with part numbers;
• that both legs raised, lowered and held the trailer after the work.

A record kept by the trailer's own unit number or VIN stays with the trailer, whichever tractor pulled it.

Log the work in Blue Collar Parts

A technician who does this work can log it in Blue Collar Parts and send the record to their customer, who confirms it. Learn what Blue Collar Parts is.

This page describes trailer landing gear service in general terms. It is not a service manual and does not establish regulatory compliance. Use the equipment manufacturer's current service documentation for equipment-specific specifications and procedures.