More from: G70 towing chain

How To Choose Chains Suitable for Towing

Tow truck operators carry specific kinds of chains for doing what they do. Along with those chains are hooks, car hauling straps, and other equipment that operators need to safely rescue and transport disabled vehicles. One thing is for sure though, not all chains are suitable for towing. Tow operators have to have either G70 or G80 chains.


The ‘G’ in G70 chain stands for ‘grade’. Industrial chains made of steel are graded according to their tensile strength. The higher the grade, the stronger the chain. A G30 chain is the weakest of the options. This is usually a general-purpose chain made for light industrial and agricultural use. The strongest is grade 100. This kind of chain is made with a strong steel alloy capable of handling heavy loads during overhead lifting.

We explain all of this to say that tow operators cannot take chances with their chains. Any chains purchased with the intent of using them in vehicle recovery have to meet minimum standards for strength. Using inadequate chains is both unsafe and illegal.

Tensile Strength and WLL

There are two factors to consider when using chains to tow or lift overhead. The first is tensile strength, a measurement of how much force an object can withstand before breaking. That is where the grading comes in. A higher-grade chain can handle more force than a lower grade chain.

A G70 grade is capable of handling 700 newtons per square millimeter. It might elongate somewhat during towing, but it is unlikely to be compromised under normal circumstances. G70 chain has a strong enough tensile strength to withstand the punishment delivered by most towing operations. Having said that, it is not strong enough for safe overhead lifting.

The second factor to consider is working load limit (WLL). Although this measurement is similar to tensile strength, it is not quite the same thing. Working load limit measures how much work a chain can actually do before breaking. If a tow truck is towing a car in a cradle, with the rear wheels still on the ground, the load being carried is less because the ground is supporting some of the car’s weight. If that same tow truck were to lift the car straight off the ground, the load would be greater.

This suggests that the same chain may be appropriate for one operation but not another. So tow truck operators have to understand working load limits in relation to the kind of stress each particular recovery will have on the chain being used. Attempting recovery operations without understanding tensile strength and WLL is dangerous.

Towing with a Passenger Car

With just this little bit of information it should become apparent just how dangerous it is to use ropes or chains to tow a disabled vehicle using a passenger car. Yet we see it all the time. You might see a four-door sedan towing a disabled SUV down city streets using nothing more than a piece of rope the driver grabbed from the garage.

Such dangerous towing is an open invitation to disaster. The driver of the tow vehicle can easily lose control; the person in the towed vehicle behind could slam into the vehicle in front by not braking quickly enough; ropes and chains can snap, etc. There is just no good way to tow a disabled vehicle without a purpose-built truck.

No, not all chains are suitable for towing. You need a steel G70 chain at minimum. If you have any plans to lift vehicles rather than simply towing them, you will need either G80 or G100.

What Is a Grade 70 Towing Chain?

We recently took the decision to include auto hauling equipment to our product line. We are now in the process of building a solid inventory of auto hauling supplies to include chains, auto hauling straps, J hooks, winches and more. One of the items we already carry is the G70 tow chain. In this post, we will explain what the chain is used for and what the grade 70 designation means.

For starters, a tow chain in the 21st century is not used in the same way tow chains were deployed 30 or 40 years ago. A standard tow chain is not meant to be the primary means of securing a vehicle to a wheel lift or flatbed tow truck. It is intended to be a safety attachment to prevent a vehicle from being completely separated from its tow vehicle in the event the primary attachment fails or becomes detached.


On a wheel lift tow truck, for example, the G70 tow chain is attached to the frame of the car being recovered after the car has already been secured to the hydraulic dolly with auto hauling straps. The tow operator may use axle or tire straps to tightly secure the vehicle. The tow chain is added as a secondary safety device. In the event of primary attachment failure, the tow chain allows for a safe and controlled stop.

Chain Grading

The G70 designation signifies that a tow chain’s tensile strength is rated at 70. A tow chain may be marked with a 7, 70, or even 700 to signify the G70 grade. With that out of the way, let us talk tensile strength for any of our readers who might not understand what that means.

Tensile strength is the maximum amount of force a chain can withstand before breaking. It is also known as break strength. The higher the grade, the greater the tensile strength of the material in question. Where tow chains are concerned, tensile strength is heavily influenced by the volume of carbon in the steel. A lower tensile strength indicates a lower carbon volume.

A typical G70 towing chain possesses enough tensile strength to safely handle a car in the event a tow truck’s primary attachment fails. But G70 chain is not strong enough for overhead lifting. This is why these chains are designated for towing rather than lifting and rigging.

Link Size and Finish

Industrial chains also come with labels indicating the chain-link size and finish. This is not necessarily important to tow truck operators, but we will discuss both just for information’s sake.

Chain-link size deals with the elongated size of each individual link. Chains with longer links might be more useful in some flatbed auto hauling applications because they make it easier to attach shackle bolts anywhere along the length. Chains with smaller links may limit shackle bolts to the ends.

As for the finish, one option is hot dipped galvanized steel. Hot dip galvanization is a process that creates chain capable of withstanding a variety of conditions, including exposure to road salt. Stainless steel and zinc-plated gold chromate finishes are additional choices for tow operators.

Now you know the basics of the G70 towing chain.  Mytee Products carries an excellent G70 safety chain manufactured by Ancra, in two different sizes. It has a working load limit of 4700-6600 pounds and conforms to ASABE and NACM standards.

For all your professional towing needs, Mytee is your leading supplier. Please contact us for anything you need, even if you do not see it on our inventory list.