Trailer jack repair and replacement gets a tongue jack cranking, holding and retracting again, or swaps a bent, stripped or dead electric jack for a new one rated for your tongue weight. Keep Them Rolling Trailer Repair handles manual and electric jacks, plus semi trailer landing gear, at homes, yards and job sites around Morris, Sussex, Warren and Hunterdon counties. Brad Smith, the owner, takes jack calls at (973) 651-1045.
Types of trailer jacks
Knowing which jack you have helps when you call:
- Top-wind A-frame jacks mount through the point of a V-shaped tongue, with the crank on top. They are common on cargo trailers, campers and larger utility trailers.
- Side-wind jacks have the crank on a gearbox at the side, which keeps the handle clear of a truck’s tailgate on short tongues.
- Swivel jacks pivot up flat against the tongue for towing and down for parking. Many have a small caster wheel instead of a foot, and they are everywhere on boat and utility trailers.
- Drop-leg jacks have an inner leg you pin at different heights, so heavy trailers and equipment haulers need less cranking.
- Electric tongue jacks raise and lower the tongue with a 12-volt motor on top, usually powered by a battery on the trailer. Most have a manual crank as a backup.
- Stabilizer jacks under the rear corners of some cargo trailers stop the box rocking while you load it.
Why trailer jacks fail
Most jacks don’t break suddenly. They get harder to turn for months, and then one day they quit. Common reasons:
- No grease. The screw and gears inside need lubrication, and many jacks have a grease fitting that has never met a grease gun.
- Water and rust. Jacks sit outside through rain, snow and road salt. Water gets past the cap and seals and rusts the screw and inner tube.
- Stripped gears. Cranking against a seized jack, or lifting more than it’s rated for, strips teeth off the gears.
- Bent inner tube. Pulling away with the jack still down, a trailer rolling while parked, or a swivel jack dropped onto the ground can bend the tube so it binds partway up or down.
- Broken swivel pin or bracket. The jack no longer locks up or down, which can let it drop while you’re towing.
- Worn caster or foot. A seized wheel, a cracked foot plate or a missing pin lets the jack sink into soft ground or skid.
- Electrical faults. On electric jacks, what looks like a dead motor is often a flat battery, a corroded ground, a loose connection, a blown fuse or a failed switch.
Repair or replace?
A jack is worth repairing when the tube is straight and the problem is lubrication, a crank handle, a foot, a caster wheel, a swivel pin or, on electric jacks, the power supply. Brad cleans and greases the internals, replaces worn outside parts and traces electrical faults back through the wiring to the battery and ground.
Replacement is the better call when the inner tube is bent, the gears are stripped, the housing is cracked, or the jack is rated for less than the trailer’s tongue weight. Grease can’t straighten a bent tube. A new jack is matched to:
- Capacity. Rated above the loaded tongue weight, with some margin.
- Lift range. Enough travel to raise the coupler over the ball on your truck and clear it when unhitching.
- Mounting. A-frame bolt pattern, a bolt-on or weld-on bracket for a straight tongue, or a swivel mount.
- Foot or wheel. A caster for rolling on pavement, a foot plate or sand pad for gravel and soft ground.
A tongue that has cracked or rusted around the jack mount gets repaired before the new jack goes on, under trailer frame repair.
Landing gear on semi trailers
Semi trailers use landing gear instead of a tongue jack. It is a pair of legs near the front of the trailer, tied together by a cross shaft and raised or lowered with a crank that has a low gear for lifting and a high gear for moving the legs quickly. The legs hold the front of the trailer up once the tractor unhooks.
Brad services landing gear. If yours won’t crank, won’t hold, has a bent leg or is missing a foot pad, call and describe what it’s doing so he can plan the visit.
Keeping a jack working
A few minutes a season keeps a jack out of trouble:
- Grease it through the fitting, or as the maker directs, at least once a year
- Retract it fully, and swing swivel jacks up and pin them, before every tow
- Put a board or jack pad under the foot on grass, gravel or soft summer asphalt
- Never use the tongue jack to lift one side of the trailer for a tire change
- Keep electric jack batteries charged and the connections clean
Jack work at your home, yard or job site
A broken jack is a strange problem: the trailer you need to move is the one you can’t hitch. That makes jack repair a natural fit for our mobile trailer repair service. Brad works across Morris County from his base in Randolph, and throughout the rest of the four-county area.
A coupler worn alongside the jack is covered under trailer coupler repair and replacement. Swivel jacks on boat trailers often get wet at the ramp and rust faster, so they’re worth checking during boat trailer repair. This page is part of our coupler, hitch and jack repair services.
Cost depends on manual versus electric, capacity, mounting style and whether the tongue mount needs work. Brad prices the job before the old jack comes off. Request trailer jack repair online or ring Brad directly.
Common questions
Why is my trailer jack hard to crank?
A jack that’s hard to crank is usually dry or rusting inside. Water gets in through the top cap and seals, and without grease the screw and gears start to bind. Try greasing it through the fitting and running it fully up and down a few times. If it stays stiff, tightens at one point in its travel, or grinds or slips, the inner tube may be bent or the gears worn. A jack in that state usually needs replacing.
Can a trailer jack be repaired or should it be replaced?
It depends on what failed. Lubrication, a crank handle, a foot plate, a caster wheel, a swivel pin and electrical faults on powered jacks are all repairable. A bent inner tube, stripped gears or a cracked housing usually mean replacement, because a bent tube keeps binding however well it’s greased. Any jack rated below your trailer’s tongue weight should be swapped for one with more capacity, even if it still works.
What does landing gear do on a semi trailer?
Landing gear holds up the front of a semi trailer when it is unhooked from the tractor. It is a pair of legs mounted behind the kingpin, linked by a cross shaft so both legs move together when the crank is turned. A two-speed gearbox gives a low gear for lifting the loaded trailer and a high gear for extending or retracting the legs quickly. Foot pads spread the load on the ground. Keep Them Rolling services landing gear on semi trailers.