Double C Slider

What it is

The Double C Slider is a gear-driven cargo tie-down winch for flatbed trailers fitted with C-channel track. It mounts into the track and slides along it, so anchor points can be positioned to suit the load after it is on the deck, rather than being fixed when the trailer is built.

Working load limit is 6,600 lb (3,000 kg).

Why a gear drive

Conventional slider winches are tensioned with a steel winch bar: the operator inserts the bar into the drum and levers against it. If the bar slips out or the load shifts, it can kick back — a long-standing source of hand, face, and fall injuries on flatbed decks.

This winch replaces that motion with a 22:1 worm gear reduction. The operator turns a handle rather than levering a bar, and working tension is reached with roughly 40 lb of force at the handle. No bar is driven into the drum during tensioning.

How it works

Tensioning happens in two stages:

1. Free-spool take-up. Turn the big handwheel by hand to draw strap slack through the mandrel. No tool required.
2. Geared tensioning. Pull the small handwheel and rotate it to the locked position to engage the gear, then use the winch handle to bring the strap to working tension.

To release, reverse the handle to take the load off the strap, then pull and rotate the small handwheel back to the release position. In the released position the small handwheel stands clear of the gear body, so the state of the winch can be confirmed at a glance during a walk-around.

Keep tensioning force below 2.5 tons. Do not substitute other tools for the winch handle — doing so can damage the gear set.

Cargo securement

The winch functions as a tie-down anchor under 49 CFR 393.104 and the general securement rule at 49 CFR 393.106. Under § 393.106(d), the aggregate working load limit of all tie-downs securing an article of cargo must be at least half the weight of that article; a 6,600 lb WLL winch contributes its full rating toward that total. The § 393.110 minimum tie-down count depends on the length and weight of the article and is a separate test — meeting the aggregate WLL does not by itself satisfy it.

Confirm both against the cargo you actually haul.

Service and inspection

Grease with Showa Shell Alvania RA-J, rated from −40 °F to 266 °F. Valvoline Full Synthetic Moly Fortified grease is an accepted alternative.

Inspect straps before every use and replace any strap that is cut, abraded, or otherwise out of service. Do not exceed the rated working load limit.