In depth analysis of off-road wheels: parameters, types, materials, and selection guidelines

In the off-road field, wheels are not just decorative components, they play a crucial role in vehicle performance and stability. When off-road vehicles gallop in the wilderness, the complex and ever-changing road conditions impose strict requirements on the wheels. Next, we will delve into the key parameters, types, materials, and selection and modification points of off-road wheels.

1、 Key parameters
size
The wheel size includes diameter and width. The common diameters are 15, 16, 17, 18 inches, etc. As the diameter increases, the tire flatness ratio decreases, and the off-road passability is improved. For example, when crossing rugged mountain roads or deep mud pits, large-diameter wheel hubs combined with large-sized tires can reduce the risk of scratching the chassis. However, when driving at high speeds, handling may be affected, and due to the increase in tire circumference, the speed of the vehicle increases at the same speed, which can interfere with the accuracy of the odometer and speedometer. At the same time, fuel consumption may also increase. The width of the wheel hub, also known as the J value, determines the range of tires that can be adapted. Different J values correspond to different tire flatness ratios and widths, which in turn affect the driving experience of the vehicle. For example, wider wheels can be paired with wider tires to increase the contact area between the tires and the ground, improve grip, but also increase the vehicle's driving resistance.
PCD and hole position
PCD refers to the diameter of the pitch circle, which is the distribution circle diameter of the wheel hub bolt holes, and the hole position is the number of bolt holes. These two parameters must be exactly the same as the original vehicle, otherwise the wheel hub cannot be installed correctly on the vehicle. Even if it is installed reluctantly, serious safety hazards such as loosening and detachment are likely to occur during driving. For example, the PCD of a certain car is 5X114.3, indicating that the wheel hub has 5 bolt holes and a pitch diameter of 114.3mm.
Offset (ET value)
Offset refers to the distance between the installation surface of the wheel hub and the centerline of the wheel hub. It has a significant impact on the appearance and steering characteristics of vehicles. If the ET value is too small, the wheel hub will protrude towards the outside of the vehicle, giving it a more aggressive appearance, but it may interfere with the wheel arches or suspension components; If the ET value is too high, the wheel hub will retract towards the inside of the vehicle, affecting the visual effect of the vehicle, and may cause friction between the tires and other parts of the vehicle during steering, while also changing the force situation of the suspension system, affecting the handling performance.
center hole
The central hole is a circular hole in the center of the wheel hub, which ensures that the geometric center of the wheel hub is consistent when installed on the vehicle axis, ensuring smooth driving of the vehicle. If the center hole does not match the vehicle axle head, the vehicle will shake while driving, and in severe cases, it may even damage the wheel hub and the vehicle's transmission system.

2、 Wheel hub type
Low pressure casting wheel hub
This is a common type in the market, which is formed by injecting liquid aluminum alloy into a mold under low pressure environment. The advantages are relatively low cost, mature technology, and the ability to meet the basic needs of most off-road enthusiasts. The disadvantage is that it is relatively inferior to spinning and forging wheels in terms of strength and lightweight.
Spinning wheel hub
Spinning process is based on casting, by spinning the wheel hub blank to make the molecular structure of aluminum alloy more compact. This type of wheel hub has good performance in terms of lightweight and strength, balancing certain performance and cost. Its manufacturing process makes the wheel quality more uniform, which can improve the vehicle's handling and fuel economy to a certain extent.
forged wheel hub
Forged wheel hub is formed by forging a whole piece of aluminum alloy through high temperature and high pressure forging. It has extremely high strength and can achieve good lightweighting, making it the preferred choice for high-end off-road wheels. However, due to the complex manufacturing process and high cost, the price is relatively high. But for off-road players who pursue ultimate performance and lightweight, the advantages brought by forged wheels, such as better handling response and lower unsprung mass, make it worth it.

3、 Wheel hub material
aluminum alloy wheel hub
Aluminum alloy wheels are widely used in the market. It is lightweight and can effectively reduce the unsprung mass of the vehicle, improve suspension response speed, thereby improving the vehicle's handling performance, while also helping to improve fuel economy. In terms of appearance, aluminum alloy wheels can present a variety of shapes and beautiful colors through various surface treatment processes. However, aluminum alloy wheels have relatively low strength and are prone to deformation or damage when subjected to severe impacts. Although forged aluminum alloy wheels have better performance, their prices are correspondingly higher.
Steel wheel hub
Steel wheels have excellent strength and impact resistance, and when facing high impact road conditions such as passing through large potholes or rocky roads at high speeds, they can better maintain structural integrity and are not easily damaged. Moreover, steel wheel hubs have good toughness, and even if a certain degree of deformation occurs, they can be repaired and restored for use in many cases. But its disadvantage is that it is relatively heavy, which will increase the overall burden of the vehicle, affect fuel economy, and the appearance design is relatively simple, with less aesthetic appeal than aluminum alloy wheels.
Magnesium alloy wheel hub
Magnesium alloy wheels have the characteristics of lightweight and high strength, which theoretically can bring better performance improvement to vehicles. However, due to its high manufacturing cost and complex production process, its current application scope in the market is relatively small, mainly appearing in high-end off-road modifications that have extremely high requirements for vehicle performance and sufficient budget.
carbon fiber wheel hub
Carbon fiber wheels are high-end products, with extremely high prices. It has high strength, high corrosion resistance, and excellent lightweight characteristics, which can greatly improve the handling and acceleration performance of vehicles. However, due to its high cost and complex manufacturing process, it is only used in a very small number of top-level off-road vehicles or professional racing vehicles.

4、 Key points for selection and modification
When choosing off-road wheels, it is important to first clarify one's off-road needs and driving scenarios. If you frequently engage in high-intensity off-road activities, such as climbing rocks or crossing heavily muddy roads, then priority should be given to wheels with high strength and strong impact resistance, such as steel wheels or high-end forged aluminum alloy wheels. If you only occasionally go off-road and spend more time driving on city roads, you can choose aluminum alloy wheels that balance aesthetics and performance. At the same time, it is necessary to choose legitimate channels to purchase wheel hubs, carefully identify the authenticity of the product, check whether the product has relevant quality certifications, and avoid purchasing inferior wheel hubs, otherwise serious safety issues such as breakage may occur during off-road operations.
Wheel hub modification is not just about simply replacing the wheel hub, but also requires dynamic balancing and four-wheel alignment adjustment. Dynamic balancing is to ensure that the wheel hub does not shake due to uneven mass distribution during high-speed rotation, which affects driving stability and comfort. Four wheel alignment is the process of adjusting the parameters of a vehicle's four wheels to meet its design requirements, ensuring the stability of straight-line driving, ease of steering, and normal tire wear. If these adjustments are not made after modification, it may lead to problems such as vehicle deviation and abnormal tire wear, which not only affects the driving experience, but also shortens the service life of tires and increases vehicle maintenance costs.
The selection and modification of off-road wheels is a systematic project that requires comprehensive consideration of many factors. From key parameters to wheel hub types, from material characteristics to selection and modification points, every link is closely connected. Only through careful selection and reasonable modification can the wheels of your car perform at their best on off-road roads, accompanying off-road enthusiasts to gallop freely.