Wheels are an unassuming component of a car. With the decreasing number of domestic vehicles equipped with steel wheels—even now, steel wheels are often only used as spare tires—many consumers no longer pay much attention to this part. However, having a basic understanding of wheels is still helpful for buying and using a car.
What is a wheel?
A wheel, also called a rim, is a cylindrical metal component inside the tire that supports the tire and is mounted on the axle at its center. Wheels come in many types based on differences in diameter, width, forming method, and material. Simply put, when you look at the side of a car, the entire wheel part—excluding the rubber tire—is basically the wheel.
Wheel Classification and Characteristics
Classified by material, wheels mainly fall into two categories: steel wheels and alloy wheels.
1. Steel Wheels
Vehicles equipped with steel wheels are usually designed with cost in mind. This is because steel wheels have lower manufacturing costs and simpler production processes. Compared with alloy wheels, steel wheels are more durable. Their disadvantages include heavy weight and high inertia, which are not conducive to fuel efficiency. Additionally, due to the structure of steel wheels, their heat dissipation efficiency is lower than that of alloy materials, which is unfavorable for brake heat conduction and may reduce braking performance. Moreover, car owners with steel wheels should not leave their vehicles parked for a long time; it is best to move the vehicle weekly to prevent irreversible slight deformation of the steel wheels.
2. Alloy Wheels
Alloy wheels are available in two forms: forged and cast. In addition to these two traditional processes, there is now a new process called MAT (Metal Spinning Technology) spin casting, and we will not elaborate on the differences between them here. The advantages of alloy wheels are obvious: lightweight, attractive appearance, good heat dissipation, low rotational inertia, and high manufacturing precision. Their disadvantages include relatively higher cost compared to steel wheels—automakers focusing on cost will abandon alloy wheels—and more complex production processes than steel wheels, as well as vulnerability to scratches and damage on the surface.
3. Wheel Maintenance
Due to the particularity of steel wheels, the wheel maintenance we discuss here mainly refers to that of alloy wheels.
Do not clean the wheels immediately after driving the vehicle. During driving, the temperature of the wheels rises due to tire heating and brake use. It is recommended to park the vehicle for a period of time and wait for the temperature to drop before cleaning.
Wheels are close to the road surface and brake discs, so they are often prone to getting dirty—usually from dirt splashed by the road and brake dust left after braking. It is not recommended to use hard brushes for cleaning; using a dedicated cleaning solution with a soft brush can easily remove the dirt attached to them. While driving, avoid potholed roads and slow down when passing speed bumps. Especially for steel wheels, driving through potholes at high speed may cause irreversible deformation. Once deformed, it may lead to body vibration at high speeds, affecting driving stability. Although alloy wheels are less likely to deform, slight deformation requires wheel balancing, and severe deformation requires wheel replacement.