Learning About Alloy Wheels

Until the past few years, most automakers fitted new models with steel wheels. These are damage-resistant and less expensive to fit, but they’re also heavier, smaller and less attractive. The “alloy” designation is typically given to wheels cast from a blend of aluminum and other metals. Aluminum is lightweight, and the other metals offer rigidity and durability. Here, drivers can learn more about alloys.

What are the Major Benefits of Alloy Wheels?

Generally, alloy wheels are better-looking, they’re lighter, and they can more efficiently dissipate brake heat. Alloys are offered in standard sizes, which means that there’s stiff competition among sellers of rims and tyres. Fitting alloys can reduce a car’s unsprung weight, which provides increased braking response and steering feel.

What is Offset?

Wheel offset is the distance between the mounting face at the wheel’s back and the centre line. The measurement is typically engraved into the wheel, and it’s given in millimetres of insertion depth. Wheels with a positive offset have a mounting face that’s toward the front of the wheel, and wheels with zero offset have a mounting face that’s even with the centre line. Negative-offset wheels have a mounting face toward the rear, and they’re commonly found on rear-wheel drive autos.

PCD

PCD is an acronym for pitch circle diameter, and it is a measurement of a circle drawn through the bolt hole centres. PCD is shown in millimetres, and it also indicates the number of studs a wheel has.

Centre Bore

The centre bore on Hilux wheels is a measurement of the hole that the hub fits into. To seat the wheels correctly, the hole must be exactly the same size as the wheel hub. Most of today’s wheels are what’s known as “hub centric”—which means that the hub bears weight. Therefore, all the bolts do is hold the wheel in place. If the wheels are “lug centric”, the bolts are more important, and they should be replaced occasionally.

Up-Stepping or “Plus Sizing”

These two terms are used to explain the practice of increasing wheel diameter while reducing tyre profile; it keeps the rolling radius unchanged. Plus sizing can improve a car’s handling, and each step reduces the ratio of tyre sidewall to alloy wheel. If it’s done well, odometer and speedometer readings remain accurate, and the vehicle will have an improved aesthetic.

The Disadvantages of Up-Stepping

In most situations, up-stepping can make the combination of wheels and Nitto tyres Australia heavier. Reducing tyre profile can also diminish the car’s damping deflection, resulting in lower ride quality. Other drawbacks include increased tyre costs, small-looking brakes and an outlandish appearance.

Alloy Wheel Fitment

Before buying a set of black rims, you should check your vehicle’s bolt pattern. Studs have various seatings, diameters and threads, and the seller should be able to offer advice. Ensure that bolt holes are lined up, that the wheel is centred on the hub and that the brake calipers and wheel arches clear properly. Lug nuts should be tightened according to the manufacturer’s specifications; tighten them ¾ of the way, lower the vehicle and finish the process.

Caring for Alloy Wheels

As anyone who’s bought a car in the past ten years can say, there are many wheel cleaners available. All claim to make wheel cleaning easier, but the key to a shiny finish is effort. Before fitting wheels, apply several coats of polish to the front and back. This can prevent dirt, dust and other debris from sticking to the wheels’ surface. Alloy wheels should be treated with the same care as the car’s paint job. After all, they can cost a fortune, and they’re under the harshest conditions faced by any part of the vehicle. Frequent washes with soapy, warm water are the best way to clean these wheels, and you should never use abrasives, steel wool pads or electric buffers. If possible, allow your wheels to cool completely before cleaning them, and steer clear of the wheel cleaners available at local car washes.

Aggressive driving can cause alloy wheels to get very hot. Their closeness to the vehicle’s braking system can make heat transfer a big issue, and excessive heat can damage the finish on these wheels. As they heat, they can expand to the point where the centre caps fall off. However, with proper care, you can keep your new alloys and other 4wd accessories looking great for years to come.