How Towing Locks Work

For whatever reason, you may need to leave your trailer alone for a while. Towing locks can protect your vehicles from theft when you're away. See more truck pictures.
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Most of us have locks on our doors at home. Protecting ourselves and our belongings from harm or theft with good locks is the first and simplest step to take when securing our houses and apartments, and they give us peace of mind when we're at home or away for a short time.

But what if you had to take all of your belongings out on the road? You'd want the same type of protection to keep everything safe, and for essentially the same reasons. If you're towing a trailer full of furniture, for instance, there'll be times when you're in the driver's seat and in control. There may be occasions, though, when you're away from your vehicle and you're faced with two separate problems -- thieves breaking into the trailer and stealing valuables, or, even worse, complete trailer theft, where someone simply unhitches your entire trailer, goods and all, and heads off down the road.

To reassure towers while they're far away from their trucks and trailers, both towing hitch locks and towing coupler locks are available. But what do they look like, and how do they work? Read on to learn about the different types of towing locks and how they're used.



Using Towing Locks

How are towing locks different than the locks we use everyday?
How are towing locks different than the locks we use everyday?

If you've ever seen towing locks, you may have noticed that they don't look like the locks you usually see. People could use padlocks to secure their hitches and trailer doors like a bicycle lock, but these types of locks are generally viewed as too easy to break. A thief could simply take the butt of an axe handle or some other blunt object and smash the lock, leaving your trailer ready for a quick inspection and seizure.

Like generic padlocks, towing locks require keys for unlocking. The driver is provided with a set of keys, and only those keys will open the lock. The shape of the locks and how they secure the vehicle are typically different, but they all usually take the place of any standard pin or simply fall straight in between matching slots on your hitch receiver. Some towing lock sets use steel pins and simple padlocks that slide together like a nut and bolt to secure tightly against the hitch or coupler. Others snap together and offer push button lock mechanisms.

Not every receiver or coupler is made the same; similarly, there are different types of towing locks. What are some of the different types of towing locks? We'll take a look on the next page.


Types of Towing Locks

Which type of towing lock is the right fit for your trailer?
Which type of towing lock is the right fit for your trailer?

Towing locks come in several shapes and sizes, and the more elaborately designed they are, the more secure and harder they'll be to break. That also, of course, makes them more expensive.

The simplest type of towing lock is the swivel lock pin, which takes the place of a standard pin and clip on a trailer hitch receiver. Swivel lock pins are short metal cylinders about 1.25 inches (3.175 centimeters) long and curved slightly at the top. This curve allows the pin to slide through the receiver's connection and have a place to rest, keeping it from falling straight through to the ground. A padlock fits on the straight end of the pin at the bottom after it's put through the receiver, and a unique key locks it in place. Because the design is simple and the materials are relatively inexpensive, swivel lock pins are pretty cheap -- they typically cost between $3 and $12.

A more heavy-duty design is the dog bone-style lock. These types of locks are shaped like dog bones -- the middle section is thin, while the two ends are thicker. One removable end acts as the deadbolt, which snaps onto one end of thin middle section secures your trailer. These are typically made of steel and have greater strength and durability, so they cost a little more at around $30.

Most locks also have some sort of debris protection, typically in the form of a rubber cap that fits over the key slot and protects it from flying rocks and other dangerous materials.

To unlock lots more information on protective towing equipment, see the next page.

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More Great Links


  • "Towing locks." (Oct. 11, 2008)
  • "Trailer hitch receiver and coupler lockset - 2" trailer hitch receiver." (Oct. 11, 2008)
  •"Trailer hitch receiver lock - padlock style for 1-1/4 trailer hitch receiver." (Oct. 11, 2008)