Trailer Jacks and Couplers: Types, Sizing and Replacement

The jack holds the trailer tongue up when it's unhitched, and the coupler connects the trailer to your ball. Both wear out, and both are straightforward to replace if you size them correctly.

Trailer jacks

Jack type How it mounts Common on
A-frame jack Top of an A-frame tongue Travel trailers and campers
Swivel jack Side of a straight tongue; folds up for travel Utility and boat trailers
Drop-leg jack The leg drops down quickly, then cranks Tall trailers needing extra lift
Electric jack Powered by the trailer battery Heavier campers

Sizing a jack

  • Capacity must exceed your trailer's tongue weight, with a comfortable margin — see tongue weight explained.
  • Lift range must reach from the ground to above your hitch ball height.
  • Mounting must match your tongue: A-frame or straight.

Replace a jack that slips, grinds, has a bent leg or a cracked mount. Browse trailer jacks.

Trailer couplers

Types

  • Straight-tongue couplers bolt or weld onto a single straight tongue.
  • A-frame couplers fit the V-shaped tongue of larger trailers.
  • Adjustable couplers let you change the tongue height to tow level.

Sizing a coupler

  • Ball size must match the ball exactly: 1-7/8", 2", 2-5/16" or 3". See ball sizes.
  • Tongue width or A-frame angle must match the trailer.
  • Rating must meet or exceed the gross trailer weight.

Signs a coupler needs replacing

  • The latch doesn't close fully or springs open.
  • The coupler rocks on the ball when latched.
  • There are cracks, heavy rust or a bent tongue.

Browse couplers, and see coupler locks for parked trailers.

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