Trailer Safety Chains?

Do they accomplish the intended purpose?  Or are trailer safety chains just a legal pain in the rear?  Maybe the better question to ask, since we’re required to use them:  “How do we make the chains more effective?“

On the surface it seems to reason that you don’t ever want your trailer straying from the tow vehicle, so with belts and suspenders as it were, the redundant connection is good.  Right?  There are really 2 parts to this . . . First, the Legal Mandate that requires trailer safety chains when towing.  And Second, the Practical and Responsible side of doing it right.  Let’s look at these 2, then some best practices.

Laws For Trailer Safety Chains

After some research, it appears the laws governing the details of trailers, including trailer safety chains, are regional (by State or Province), yet all (that I could find) require safety chains.  Most of the laws are consistent across the board, but some have slightly different details.  For instance, some states actually require “chain”, yet cable appears to be a legal substitute in others.  Some mandate a particular type of hook (or more to the point, retainers on hooks), others do not.  Some dictate how chains must cross; others do not.

All that said, it’s worth reading your area specifics to know what is required.  One interesting thread about laws in Texas point out a law about crossing the chains under the hitch, but that portion of the regulation was not in the same document as the rest of the law on trailers.  I’m not sure how citizens are to know that, but . . . .

Well, let’s not bog down.  The truth is, if you responsibly act so your loads are secure, then you probably won’t have trouble.

Being Practical And Responsible

Of course, towing adds a measure of responsibility to driving.  Making sure everything safely connects is the first part of that.  It is very unfortunate when we see terrible accidents involving trailers, yet they continue to occur.  It only takes a moment of distraction or absent mindedness to miss part of the connection process.  However, there are several things we can do to minimize the potential.

First:

Use the right equipment.  Starting at the hitch, make sure it is securely on the tow vehicle.  Make sure the hitch and the vehicle are rated to tow your trailer and load.  Check that the ball is secure (tight, etc.).  And, on this topic, make sure the ratings of the safety chains are greater than the load.

Second:

Choose proper components.  From a DIY perspective, this especially important:

• Many times I see the last link of a chain welded to the trailer frame.  Sounds good, but welding induces extreme heat, and that changes the temper, reducing strength.  This makes the last (attaching) link the weakest.  Don’t do this.
• Attach chains to the trailer tongue in a way they naturally accommodate forces in – fore and aft – and side to side.  Don’t attach them in ways where the forces will bend or break the attaching elements.
• Also, don’t attach safety chains to the bottom of the tongue where they will grind off if the trailer tongue is scraping the ground.
• Use the right length of chain.  This sounds obvious, but there is a lot to it.  For instance,  the “Right” length for a bumper hitch may not be “Right” for the same trailer with a drawbar.  For this reason, I recommend that chains are NOT permanent.  Instead, use connecting links (rated higher than the chain) so you can adjust length.  Or one of these Good Ways to Shorten a Chain.
• Don’t twist the chains to modify length.  This is a bad idea on several levels which we discuss in this post on Chain Twist.

• 

  Trailer safety chains are only as strong as the weakest link.  That is not just links of the chain.  It includes attachment at both ends.  If you use hooks, make sure they are rated above the chain, and avoid open hooks.  Also, make sure to attach to something of substance, both on the trailer tongue and on the tow vehicle.

Third:

Follow the Best Practices for Trailer Safety Chains in the section below.  Also read this other article about where and how to attach the chains.  The article shows many ways – both good and bad.

You can make your own attachment method, or there are products available to purchase specifically for this.  Here is a review of the Link Lock system as one example.

Alternatives

When installed and used properly, chains provide an extra measure of safety for towing trailers.  However, there are many people that don’t like trailer safety chains — not because of safety, but because implementation is so often improper.  So what are the choices?

Cables

Cables are becoming more and more accepted.  They offer a quieter approach, and they can be much stronger for the size and weight.  The big drawback is length.

Cables don’t adjust for length, and you can’t fit them to be the right length.  (I suppose you could cut them and re-do the swedging, but how would you know if your DIY swedge job is strong enough?)

Conceptually, straight cables are pretty cool, but they would have to be made specific for each application so length is right.  Coiled cables are actually quite long when they uncoil before they do their job.

Finally, cables as a substitute for chains are not allowed in all areas, so check your local laws.

This image of cables is from Curt Manufacturing.  Curt makes a lot of really great products, but this is not one.  At Mechanical Elements, we do not recommend coiled cables like these.

Other Inventions

There are several inventions that people have come up with to eliminate the chains, and in many cases, make towing even safer.  Some of the inventions are cool, but they must overcome the legal and governmental inertia to use them.  Right now the law says “Chains”.  Cables are a reasonable stretch for some small minds, but for other devices . . . . well, they can’t think that far.  Too bad, because in the spirit of safety, innovation to conquer the shortcomings of trailer safety chains seems like a good idea.

Best Practices With Trailer Safety Chains

So, it’s required by law.  And, it’s a good idea — because you don’t want to be responsible for killing someone.  Chains may not be the greatest, but they definitely stack the deck in your favor.  I can’t tell you all the stories I’ve heard and read about how trailer safety chains have saved the day.  With that in mind, here is a good list of best practices with chains.

1. The first step is to use the right equipment.  See the above section on Being Practical And Responsible.
2. For the DIY builder, implement the chains, including attachments, as in the section on Being Practical And Responsible above.
3. Be sure your trailer safety chains meet the right classification, “Class”, according to Gross Vehicle Weight Rating, GVWR.  For the trailer, GVWR is the total capacity, including the weight of the trailer itself.  A purchased trailer should have the GVWR on an attached placard.
4. If your chains have hooks, make sure they are of at least the same rating as the required chain.
5. If your chains have hooks, make sure there is no way to bounce, rattle, shake, or otherwise come loose.  Believe it or not, this is a big problem.  There is a right and a wrong direction for attaching the hooks, so learn the right way.  Optionally, and additionally, use hooks with spring retainers, rubber straps, etc. so the hook cannot come off.  See orientation in the image and description above.
6. Trailer Safety Chains should be as short as practical.  To measure, attach the trailer in an “almost Jack-knifed” condition, and set the chain length to the furthest connection points.  The chain should not be tight, but should not have much slack either.  Too many times we just use and accept the chains that come with the trailer without thinking about the implications.  Shorter (within reason) chains are safer in several ways.
7. DON’T allow chain to drag the ground.  In many cases, especially for vehicles with lower hitch points (cars and minivans) chains of proper length will still drag the ground.  If the chains are the right length, then yes, you can hold them up with a bungee cord, zip-ties, or something similar.  This convenient doo-hicky is worth considering.  Also see point 8 about bungees.
8. NEVER twist trailer safety chains.  If they are too long, double them back through the hitch chain loops, or use connecting chain links to effectively shorten the chain.  DON’T use zip-ties to gather extra links because if you need the chains, the zip-ties break and the long chains will make it much harder to control.  Also, DON’T use Bungees to hold up chains that are too long.  See point 7.
9. NEVER spread a chain link to fit an oversized bolt.  It weakens / damages the chain, and the bolt won’t go to the end of the link where it can effectively hold the load.  Much better to use a connector to give a larger effective “link”.
10. When attaching chains with bolts, use only the highest grades — like Grade 8 bolts.  There is no reason to ever short-cut these important connections.  (Also, Threaded Rod for Custom Bolts is awesome, but not for serious places like trailer safety chains.)
11. As you connect things, make sure the cable (or chain) to the emergency brake box, Breakaway Actuator (if so equipped), is shorter than the trailer safety chains.  You definitely want that to activate in an emergency.  If that cable is longer than the chains, it will never activate.
12. Cross the chains when attaching — left to right and right to left — but don’t twist them up.  Crossing helps with turning especially if the connection points have wide separation.  Don’t buy into the idea that crossing will cradle the hitch if separation from the ball occurs — that is only true in some cases where heights and lengths are perfect — which is not usually the case.  However, it will help with minimizing chain length, and it will help in control if the chains are actually needed.  (Control, because the crossover reduces the range of freedom for the trailer tongue.)
13. Trailer Safety Chains are for the emergency we hope never happens.  Treat them as if your life, and your families life depends on them.

Why Do I Use Safety Chains?

In times past, I disliked “trailer safety chains”.  It seems like a silly duplication.  However, I’ve come to realize the safety chains are not there in case the hitch fails, they exist in case I fail.  That’s right.  If I fail to connect the hitch properly, or if I fail to seat the ball, or if I fail to connect or tighten something, then the chains are there to compensate for my screw-up.

It would be so horrible if someone died because I overlooked something — and death is not an uncommon result of such a screw-up.  Yes, I use trailer safety chains now happily — to protect myself from myself.

One other dreadful thought to support the Why Use Trailer Safety Chains — read this article about dangling from a bridge by a single chain.  It still gives me the shivers.

Twisting Trailer Safety Chains

The next post is about what really happens when twisting safety chains.  That’s an all too common practice that introduces some dangerous side effects.

And, speaking of avoiding dangerous issues, the next good article to read is about the Trailer Breakaway Kit.

If you want some good ideas about ways to attach trailer safety chains to your trailer tongue, we have a few good articles.  First is “How to Attach Safety Chains.”  The next is “Improving Trailer Safety Chain Connections“.  The third is Free Plans for an Adjustably Permanent Chain Anchor System.

Be Safe Out There!