Are heavy cars compromising our safety?

Loading up your car with the maximum number of occupants, a boot full of gear and a fully-laden roof rack is a bit like going for your usual jog with a 20kg pack on your back. Load matters.

When was the last time you thought about the impact a full load has on your car’s safety? Do you even know what your car’s gross vehicle mass (GVM) is?

At a recent event, Supercars commentator and Pedders representative, Neil Compton, spoke with carsales about the importance of understanding your vehicle’s limits in a market that favours connectivity and comfort amid a hap-hazard approach to safe driving.

With all this comfort and clever safety equipment to speak of, it begs the question: are we leading people to think that driving is nothing more than starting, stopping and steering?

“The driving demand actually requires the polar opposite… You have to be in a heightened state, ready to be able to do something on a defensive basis,” says Crompton, an ambassador for the suspension brand for over 12 years.

“The hard part is that most people regard their licence as a right, not a privilege.

“You do your basic training [most often] very young, knock off the simple questions and you’re a driver for life. Sometimes, sadly, the first time somebody actually experiences a vehicle in a dangerous dynamic state can often sadly be their last.

“Or if not so grave, then at least a nasty accident [unfolds]. You hear and see it all too often and too close to home,” he says.

“Consider tradies, for example, and their pre-fabbed utes. Very often as soon as they put their gear in, they’re overloaded. Stopping distances go out the window, roll control goes out the window and it’s just not [something that is] understood.

“And the [Pedders] company is having great success with that message. When you actually feel it, you understand.”

Education and practical experience is key. To this end, Pedders recently hosted 50 of its distributors and guests (including carsales) to feel first hand the difference that appropriate suspension and brake upgrades can make to laden vehicles.

On hand were a variety of vehicles fitted with manufacturer’s original equipment, the same vehicles laden and then a laden vehicle fitted with Pedders’ equipment upgrades.

With a focus on vehicles that double as workhorses, we drove the Ford Ranger, Volkswagen Amarok, Toyota HiLux, Holden Colorado, Isuzu D-MAX and a light commercial vehicle in the form of Toyota’s outgoing HiAce.

The activities at the event at Sandown (in Melbourne’s east) included emergency braking, slalom stability tests, a double-lane change emergency manoeuvre, corner braking and rough track driving.

Tested back to back, the modified vehicles featured the Pedders GVM+ Kit that upgrades a vehicle’s front and rear shock absorbers, springs, shackles, U-bolts and bushes.

Some of the test vehicles added brake upgrades that saw a big front brake kit and drum to disc rear brake conversions.

Check out the leaf springs on that, said nobody ever. It’s not the usual (sexy) aftermarket chatter we’re used to hearing about.

But back-to-back testing proved just how much a heavy load can effect a vehicle’s steering, braking and suspension. These things, combined, dramatically change the overall control of a vehicle.

“I’ve seen it first hand how important it [education] is,” says Crompton.

“What the industry has done, knowing it can’t make better quality drivers, is the distinguishing features between passive and active safety -- making the cars safer. Because trying to educate the car parc is near impossible, but in truth is should be a bit of both

“When I grew up it was a miracle for cars to be able to stop without smouldering brakes… Now you can buy a new car for $20K, no more to pay, do hot laps of the country and maybe do an oil change,” laughs Crompton.

Crompton contends our get up and go mentality rarely allows time for careful consideration of the changing demands we put on our car – adding a load, in particular.

“We’re all pre-programmed – and cars are portrayed as an instant can-do solution. Pedders have recognised that’s an issue,” says Crompton.

So what can you do about it? Simple: understand you car’s GVM and don’t exceed it. And if you’re regularly approaching the limits of your car’s maximum load, consider an equipment upgrade or maybe a different vehicle.

Most importantly, appreciate that your vehicle will behave differently when under load.