How Should Safety Chains Be Used With A Trailer Hitch?

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You are about to hook up a trailer to tow a heavy load, but you might need some chains. How should safety chains be used with a trailer hitch?

Safety chains are mounted from the trailer frame to the tow vehicle. They act to keep the trailer close should the coupler disconnect from the hitch ball. The chains allow the tow vehicle’s driver to guide the trailer to a safe spot. Most states require the use of safety chains when towing.

The NHTSA reports over 50,000 accidents involving trailers hitched to light-duty vehicles happen annually. While this might seem like a low number considering the millions of people who tow every day, the fact that there are any problems is one too many. Whether you are pulling a boat, camper, or equipment, you can do some things to increase your chances of reaching your destination. While you should always double-check to ensure your coupler is fastened to the hitch ball correctly, a good pair of chains can be a backup if the trailer connection fails. How do you put safety chains on? Where do they go? What size of chains should you use? Let’s explore the issue of safety chains and why they are essential to towing a trailer.

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Why Are Safety Chains Important?

Safety chains act as a backup means to keep the trailer connected to the tow vehicle should the coupler fail, and the connection is broken. The safety chains can help keep the trailer close as the driver finds a safe stopping point. The chains keep an accident from happening due to a runaway trailer.

How Do Safety Chains Work?

Anytime a person seeks to tow something with a trailer, there must be some kind of connection point between the trailer and the tow vehicle. In most cases, a trailer’s tongue connects to the hitch ball of a tow vehicle. The coupler at the end of the tongue rests on top of a receiver ball and locks into place. (A tiny lever snaps down, locking the coupler over the ball. A small cotter pin prevents the latch from popping back up and loosening the coupler). This hitch ball can still pivot when the tow vehicle turns, so the trailer follows in the same direction.

What might happen if the coupler becomes disconnected? This situation is where safety chains come into play. The chains are criss-cross in an X pattern hanging below the tongue and tow hitch. Should the coupler give way or the hitch break off, the trailer is pulled by the truck through the safety chains.

While chains are never a substitute for the connection of trailer coupler and a hitch, they can provide enough connection to pull a trailer to the side or off the road.

How Do You Connect Safety Chains to A Trailer/Tow Vehicle?

There are a couple of things to remember when using safety chains to hook a trailer to a tow vehicle.

Use An Adequate Chain Link Size

Every chain has a breaking strength. You want to ensure your chains are strong enough to do what they might be forced to do. If a coupler/hitch breaks, you want a chain that will not snap from the force of a trailer that suddenly has a mind of its own. The chain links should be rated for the maximum gross vehicle weight rating of the trailer. For example, a 5000 lb trailer should have chains rated for that amount. You want them to be thick enough not to break but remain connected to the truck and trailer.

Most trailers are sold with safety chains installed, but if they aren’t there, you’ll need to choose a link thickness made from high-quality steel that works well and is rated for the maximum weight.

Choose the Correct Length

Safety chains should have enough slack to hang below the trailer tongue but not enough to scrape the ground. (When safety chains drag on the ground, they create sparks from scraping the concrete. The friction wears the chain down and affects its integrity, not to mention the sparks that create a dangerous situation whenever gasoline vehicles are involved).

A chain that is too long will not be effective in keeping a trailer from swerving into the lane of oncoming traffic. Should a chain be too short, there isn’t enough slack for maneuvers like turns, and steering becomes compromised. While the proper length will vary depending on the size of the trailer, you should plan to leave enough slack so that the trailer will stay connected but not enough to allow the trailer to become a flying projectile.

Connect the Chains Correctly

You should always use the bolt tabs provided on the tow vehicle to connect your chain. These bolt tabs are welded to the frame rather than the chain, providing solid connectivity to the tow vehicle. (Trailers often have bolt tabs welded onto the tongue). You should use a thick bolt, spring washer, and nut that will keep the chain in place.

Criss-Cross the Chains Under The Tongue

This thought might seem like a small detail, but it is critical. The reason for arranging the chains in an X pattern is that you never know which way a trailer might run once it gets loose. You want the chain on the left of the trailer’s tongue to be hooked to the truck’s passenger side frame. This connection allows opposing forces (the trailer’s drag and the pull of the tow vehicle) to keep the trailer from getting too far sideways. The criss-cross provides a balanced pulling force and the trailer stays straight behind and attached to the towing vehicle.

In addition, crossing the safety chains helps keep the trailer tongue off the ground should the coupler become disconnected. Since the trailer tongue is heavy, it will immediately drop toward the ground when it becomes unconnected. So, if you don’t want the trailer tongue to be ruined by scraping across the concrete, you need a safety chain that will keep the tongue off the pavement.

Do I Have To Use Safety Chains When Towing?

Most states have regulations requiring safety chain use when towing a loaded trailer. You should assume that your state requires them and plan on using a safety chain since they can be effective in helping you maintain control should an emergency occur.

Can I Tow With Only Safety Chains?

Safety chains are great for use in an emergency situation, but they are not designed to tow over longer distances. They are best used as a fallback contingency to avoid an accident on the highway.

Do Safety Chains Come in Sizes?

Most trailer manufacturers have trailer chains in pre-made sizes for both length and weight loads. While there is no practical method for calculation of what size is best, a simple measurement from the left side of the connection point (bolt tab) to the right side of the trailer tongue (don’t forget to add several inches for slack) is a great place to start. If in doubt, contact your local trailer manufacturer or dealer and let them advise you as to what is the best length.

As far as chain strength is concerned, chains vary in weight ratings. You should purchase a chain that is rated for the maximum gross weight of the unit you are towing.