What is an anti-roll bar and what does it do?
Thursday, 27 June 2019
An anti-roll bar, also known as a sway bar, is a feature of the suspension system.
It is a particularly well-named component, as it is designed to do exactly what its name suggests – prevent, or mitigate, the rolling (or swaying) of the car and improve the vehicle’s handling.
No doubt you will have felt a car sway from time to time.
It’s a sensation that most often occurs when you navigate a corner or a roundabout and is especially obvious when doing so at speed.
When you take a turn at a decent clip, you can feel your body shifting to the outside of that curve.
Take a left turn, for example and, as an Aussie driver, you’ll feel yourself shifting toward the driver’s door.
This weight transference in corners also happens to the car as the sprung mass of the vehicle – that is the parts of the car that are supported by the suspension, including the vehicle’s body, cargo, and you – shift as the car moves into a turn.
In extreme circumstances - say too much speed entering a corner or with an overloaded, top-heavy vehicle – this can lead to the car rolling over.
HOW DOES AN ANTI-ROLL BAR WORK?
An anti-roll bar is a piece of tubular metal, curved in a very broad U-shape, that connects the suspension on one side of an axle to the other through the use of link rods, also known as end links.
These link rods are fitted with a ball joint at each end, which allows them to move with both the anti-roll bar and the rest of the suspension during cornering.
As a car enters a corner, the bar experiences a twisting effect that counteracts the roll effect, working to compel each side of the vehicle to lower or rise to similar heights, keeping the car as level as possible with, hopefully, its wheels on the ground.
Keeping all four wheels connected to the road allows other suspension components – from the shocks to the tyres to steering – to work as a they were intended and provide better handling and a safer drive.
If you feel your vehicle is not handling like it should, you can find the workshops with the skills to inspect and repair your vehicle on AutoGuru.
Jonathan has been writing about the auto industry for years and is particularly interested in the high-tech innovations sweeping the industry.
He’d love to own a Tesla Model S, but also adores anything with a V8 under the bonnet.
He has yet to decide between an EV or a Mustang for his next ride.