Towing Safety: How to Determine the Towing Capacity of Your Vehicle

What better way to explore the great Australian wilderness than with a powerful vehicle towing a trailer or caravan containing all the mod-cons and home comforts needed to enhance the experience? At RV Parts Express, we have a fantastic team of dedicated outdoor enthusiasts with incredible knowledge of all aspects of camping and other outdoor activities. We asked for tips on determining the towing capacity of any vehicle and why it is an essential part of safely towing any trailer. Here is a synopsis of their thoughts and comments.

First things first: What is towing capacity?

Your vehicle’s towing capacity is the maximum weight it can pull safely without negatively affecting its performance or balance. This figure can vary depending on certain contributing factors we will address in this article, including:

• The vehicle’s intended use — Family sedans can pull a reasonable amount of weight but are not designed to do so. A 4WD vehicle with a tow bar is carefully engineered to be excellent at pulling trailed weights, and its gear ratios and torque levels will be adjusted accordingly.
• How much existing internal weight it carries — If your vehicle is packed to the brim with heavy items, it is already working harder to move than when empty, reducing its overall towing capacity.

Vehicle manufacturers will provide an estimated towing capacity for each vehicle they produce and sell, which will only apply in some situations. It should also be noted that they will assume (for the sake of more impressive figures) that the vehicle contains only a driver and no additional internal loads. It is, therefore, crucial to be able to do your calculations based on what you know about the vehicle, its contents, and the intended trailer.

Calculating towing capacity

• To calculate the maximum towing capacity of any vehicle, you must first know its official gross vehicle weight rating (GVWR) or the maximum weight that your vehicle can physically move, including its own. Your owner’s manual will contain the figure you need; failing that, check the driver’s door panel, and you will likely find the gross vehicle weight rating and other pertinent information.
• You also need to know its sitting or ‘kerb’ weight, including all the cargo carried, from passengers to windscreen-washing fluid and everything in between.
• Subtracting the vehicle’s kerb weight from its GVWR will give you the towing capacity, and you would do well to heed the manufacturer’s advice never to exceed it. When we spoke with the team here at RV Parts Express, they unanimously agreed that you should never come close to the towing capacity of your vehicle if you wish to avoid problems. Coming within 10% of its maximum capacity is close enough.

Why is it dangerous to exceed a vehicle’s towing capacity?

As powerful and seemingly invincible as modern vehicles can be, each has its limit that it is dangerous to stray beyond. Cargo loads can shift unexpectedly when road conditions or actions cause sudden movements. If the vehicle is straining to the absolute maximum and likely unbalanced, its ability to recover form and power through sudden weight shifts is drastically impaired.

Law enforcement officers are singularly unimpressed by individuals who blatantly ignore the GVWR of their vehicle, putting themselves and others at risk. You can expect a ticket at best, and much worse if you are involved in an accident, and your vehicle is badly over-laden. You have been warned.

• Remember - Your tow vehicle and trailer each have their own GVWR, and it is possible to overload both, doubling the risk.

Braked towing capacity

A huge caveat in the rules regarding a vehicle’s towing capacity comes when the trailer has brakes that can be operated from the towing vehicle. By hooking the electrics of the trailer to the primary vehicle, the brakes work in tandem and provide much more stability and stopping power. Heavier weights can now be safely towed without sacrificing vehicle control or increasing the risk of accidents.

How much towing capacity do you need?

It may seem obvious, but you need a higher towing capacity than the heaviest weight you intend to pull. The lead vehicle must be powerful, and the hitch strong enough to handle whatever weight is attached. The trailing weight must be balanced to prevent massive pressure on the point where the two connect. If you have an enormous caravan loaded to the gills with more camping equipment than most people have ever seen, the chances are a fair bit of weight is involved. Make sure you know exactly how much, even taking it to a haulage station if necessary and having it officially weighed. The consequences of misjudging your vehicle’s towing capacity can be severe, and losing control of an unwieldy, overloaded vehicle in inclement weather conditions is terrifying.

How to safely maximise your vehicle’s towing capacity

Some optional changes you can make to increase towing capacity include:

• Upgraded hitch — A weight-distribution hitch is handy, but an upgrade of any description should increase your pulling power.
• Larger brake pads and rotors — A simple way to increase stopping power and load capacities.
• Better axles — Sturdier axles on your towing vehicle allow for increased pulling power.
• Add a bigger radiator — Your engine strains when towing; improve its cooling capacity and expect a noticeable improvement in pull.

Conclusion

So many rugged vehicles in Australia can tow huge weights that it’s easy to neglect to check them carefully, which can be a serious error. Take a few moments to ensure your towing vehicle can safely pull your fully-laden caravan or trailer, and never assume it will be acceptable to continue simply because it seems to handle the weight. You may put a dangerous strain on your equipment, leading to unpleasant or even fatal consequences.

Contact us

If you think you’re ready to do some towing of your own and need any additional parts or accessories, please take a few moments to browse our extensive collection, and you’ll get lost in a world of game-changing, innovative products. Feel free to contact us with any questions or comments; we’re ready and waiting to help in any way we can.