How Tow Hooks Work

Tow hooks are very simple tools -- they're just hooks that are bolted to the frame or mounted onto the receiver of a vehicle. The frame or the receiver is typically the only spot on a vehicle on which it's OK to attach tow hooks. Other places like bumpers or wheel axles simply aren't built to support the force of another vehicle pulling on them. The U.S. Department of Transportation (DOT) requires that every American-made vehicle has four attachment points in their frames, and it's through these holes driver can bolt their hooks. If for whatever reason you don't want to use these holes, you can also weld tow hooks onto the frame if you have the skills to do so.

Once the hooks are mounted onto the frame, an appropriate set of straps is necessary for making a connection and allowing one vehicle to pull the other. There are actually two types of straps used in towing -- tow straps and recovery straps -- and it's important to know the difference between them. Tow straps are designed for, as the name suggests, towing. The straps come with a hook on each end, and they won't stretch. If you're pulling someone out of a rough spot while off-roading, these types of straps are not recommended because of safety issues -- more on that in the next section.

That's what sets them apart from recovery straps, which are the type of straps recommended for pulling out a vehicle that's stuck in the mud. Recovery straps have loops instead of hooks, and they're designed to stretch when pulling another vehicle. They slip right over the towing hooks securely, and when the vehicle doing the pulling starts to move, the recovery strap will stretch. Just like a rubber band or a Slinky, the strap wants to return to its original position when it stretches, so its energy is transferred to the immobile vehicle, pulling it out.

Using towing hooks and recovery straps seems pretty straightforward, but there are a few safety considerations to keep in mind that will protect both you and your vehicles from damage.

There are several precautions to take before using tow hooks and recovery straps with vehicles. As mentioned before, the placement of your tow hooks is very important. The only place on a truck or SUV that can really handle pulling the weight of another vehicle -- an object that typically weighs several thousand pounds -- is the frame. Bumpers, especially modern ones, are made out of plastic and other relatively soft materials, which bend easily. Trying to recover a vehicle by pulling on its bumper will either significantly deform the bumper or pull it straight off. Pulling from an axle also isn't recommended; although it may seem like a sturdy part of the car, but it can be easily bent or ripped off, as well.

It's important to use the right type of strap to recover a vehicle. Towing straps have metal hooks. If your friend's car gets stuck in the mud and you try to pull it out with a tow strap, there's a possibility that the metal hooks can snap away. If this happens, the strap can fly anywhere, and if someone is standing outside of either of the vehicles, he or she could be seriously injured by a flying hook. Recovery straps are designed for this special use. They don't have hooks, stretch and are much lighter than tow straps, so they're less likely to snap off and hurt someone.

It's also a good idea to check both tow hooks and recovery straps for wear and tear before you use them. Tow hooks should be free of rust, grime and any defects, and you should inspect recovery straps for any cuts, frays or dirt.

Finally, good driving techniques will effectively determine the outcome of the recovery. The person doing the pulling should drive slowly, not quickly, applying light pressure to the gas pedal. Quick, jerky movements can potentially damage the strap or either of the vehicles. There should also always be someone located in the driver's seat of the vehicle being pulled to provide better control once it's out of its spot.

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

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