Replacing a trailer coupler latch lock? The latch-hole diameter, working span and locking-head clearance must all match. Trimax TC and SXTC coupler locks include fixed-span models and adjustable versions; the span is not the trailer ball size.

Three checks before buying a coupler latch lock

Check the latch opening. Confirm the hole diameter and its position in the closed latch. Measure the locking span. Record the distance that the pin must cover, including room for the lock head. Identify the mechanism. Make sure the chosen lock can be installed without preventing the coupler from fully latching.

Size note: Trimax lists the adjustable TC123 and SXTC123 at three distinct span settings: 7/8, 2-1/2 and 3-1/2 inches. Do not assume an infinitely adjustable width. A lock also does not repair a worn or damaged coupler.

Trimax TC and SXTC part-number chart

MPN Working span Construction Configuration
TC1 Up to 7/8 in Steel Fixed
TC2 Up to 2-1/2 in Steel Fixed
TC3 Up to 3-1/2 in Steel Fixed
TC123 7/8, 2-1/2 or 3-1/2 in Steel Adjustable
SXTC2 Up to 2-1/2 in Stainless-steel series Fixed
SXTC3 Up to 3-1/2 in Stainless-steel series Fixed
SXTC123 7/8, 2-1/2 or 3-1/2 in Stainless-steel pin Adjustable

Steel versus stainless-steel options

TC1, TC2 and TC3 are fixed-width locking pins in the steel series, offered for up to 7/8, 2-1/2 or 3-1/2-inch spans. TC123 offers three selectable working spans in a hardened-steel model.

SXTC2 and SXTC3 are stainless-steel models for up to 2-1/2 and 3-1/2-inch spans. SXTC123 has a forged stainless-steel pin with an adjustable locking head. Choose by exact part number, not appearance alone.

Find the exact Trimax coupler lock

Before towing or storing a trailer

Verify that the coupler latches securely on the correct hitch ball, the lock is positively engaged and the release lever cannot open. Follow the coupler manufacturer's operating instructions. Coupler latch locks are separate from receiver hitch locks and full-surround coupler security devices.

Looking for a receiver lock instead? Compare the Trimax receiver-lock size guide. For another latch-lock family, see DeadBolt coupler-lock dimensions.

Common questions

Does a 2-inch ball coupler need a 2-inch latch lock?

No. The ball diameter and latch-lock span are different dimensions. Measure the latch assembly.

Does TC123 fit every width between 7/8 and 3-1/2 inches?

Trimax specifies three span settings. Verify that one of those settings matches your latch and allows proper locking.

Can a receiver hitch pin replace a coupler latch lock?

Not as an assumed substitute. The intended applications and locking dimensions differ.

Quick part links: TC1 · TC2 · TC3 · TC123 · SXTC2 · SXTC3 · SXTC123

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