Any reliable car mechanic will tell you that a wheel alignment is an important part of your vehicle’s regular maintenance schedule. But how can you tell when you need an alignment and why is it so important? Well, let’s find out.
What is a Wheel Alignment?
A wheel alignment is a series of measurements and adjustments to the suspension and steering designed to ensure that all four wheels are parallel to each other and perpendicular to the ground, or as close to parallel and perpendicular as manufacturer specifications indicate.
Properly aligned wheels will minimise the resistance your tyres create with the road, helping them to roll smoothly.
There are three main measurements involved in a wheel alignment: camber, toe and caster.
Camber is the inward or outward angle of the tyre when viewed from the front of the vehicle. Camber can be negative or positive. Negative camber is when the top of the tyre leans in towards the body of the vehicle. Positive camber is when the top of the tyre leans away from the body of the vehicle. Most road cars will have a slight negative camber to counteract the forces on the tyres when cornering.
Automotive toe refers to the amount tyres turn inwards or outwards when viewed from above. If you look down on your tyres from above and they are pointing inward, that’s toe-in alignment. If they are pointing outward, that’s toe-out. The toe angle determines the direction of the tires compared to the centerline of the vehicle. Toe is the most critical measurement for tyre wear and also has a significant effect on vehicle handling.
Caster refers to the angle of the steering axis when viewed from the side of the vehicle. Positive caster means the angle of the steering axis is tilted towards the driver, whereas negative caster means the steering axis tilts away from the driver. Most vehicle specifications call for a slight positive caster. Caster helps to balance steering, stability and cornering. It can improve vehicle control, maintain straight-ahead direction and help with steering wheel self-centering. Caster has little effect on tyre wear.
Why is it important?
Your wheel alignment is important for a number of reasons.
- Minimises tyre wear
Misaligned wheels increase tyre wear and can cause uneven tyre wear, meaning you could be replacing your tyres more often than you need to.
- Improves fuel efficiency
Properly aligned wheels make for a smoother ride with less friction, which reduces fuel consumption.
- Improves handling and safety
When the wheels are properly aligned, the vehicle will steer, corner and handle better, which reduces driver fatigue and improves vehicle safety.
- Enhances ride comfort
A wheel alignment means a smoother ride, a reduction in vibration and shock through the steering wheel and less noise from the steering and the wheels.
What makes Wheels go out of Alignment
Your tyres are your car’s only direct points of contact with the road. As such, they are subject to a range of incredibly strong forces. And it only takes a tyre shifting one-sixth of a degree for it to be considered out of alignment.
The most common cause of misaligned wheels is normal wear and tear. Over time, suspension components will wear out and parts will shift, leading to minor movements in wheel alignment.
Of course, driving habits and terrain can speed up this wear and tear. So if you spend a lot of time driving on rough roads or you’re a rough driver, you may find yourself needing wheel alignments more often.
Tyre wear can also affect your wheel alignment. Tyres tend to wear out unevenly. As the diameter and width of the tyres changes, the wheels can start to pull in slightly different directions and these pressures can affect the alignment of the wheels.
Another common cause is hitting something with your wheel or tyre. A sharp knock to your wheel or tyre, like hitting a curb or pothole while driving, can immediately throw out your alignment.
Finally, any work your mechanic does on your steering, suspension or tyres can affect the alignment of your wheels, so it’s important to ensure that a wheel alignment is carried out after any of this work.
Signs you may need a Wheel Alignment
There are a number of clear signs that you may need a wheel alignment. These include:
- Uneven wear to your tyres
- Vehicle pulling to the left or right when you drive
- Off-centre steering
- Steering wheel vibration
- Loose vehicle handling
- Squealing tyres
If you notice any of these signs, you should contact your local mechanic as you may be in need of an alignment.