Complete Guide to Tire Selection

Tires, as the only part of a car in contact with the ground, directly affect a vehicle's handling, safety, comfort, and fuel economy, serving as the "cornerstone of safety" for automotive travel. Mastering core tire knowledge not only helps consumers accurately select suitable products but also extends tire life and reduces travel risks through scientific maintenance.

Modern tires are primarily radial tires, with a core structure consisting of "outer tire + inner tube + belt" (tubeless tires are tubeless). The outer tire is the core of performance, composed of the tread, sidewall, carcass, belt layer, and bead.

The tread is responsible for grip, water drainage, and noise reduction; the rubber compound determines wear resistance and wet-weather performance; the main drainage grooves affect drainage in rainy weather; the sidewall displays parameters and provides cushioning; its thin material is easily damaged, and bulges or cracks require immediate replacement.

The carcass is the "skeleton," composed of multiple layers of cord fabric; the material and number of layers determine load-bearing capacity and impact resistance. The belt layer is a core innovation of radial tires, using high-strength steel wires to fix the tread, improving high-speed stability and delaying wear. The tire bead secures the tire to the rim and affects the seal of tubeless tires; the inner tube seals the air. Tubeless tires use a bead seal, offering superior safety and durability, making them the mainstream choice for passenger cars.

Tires are classified in various ways. By application, they can be categorized as passenger car tires, commercial vehicle tires, construction machinery tires, agricultural tires, etc. Passenger car tires can be further subdivided into sedan tires, SUV tires, and sports tires. By tread pattern, they can be classified as longitudinal, lateral, asymmetrical, and unidirectional.

Different patterns are suited to different scenarios—longitudinal patterns offer excellent water drainage, suitable for rainy areas; lateral patterns provide strong grip, suitable for unpaved roads; asymmetrical patterns balance handling and quietness, widely used in family cars; unidirectional patterns offer outstanding high-speed stability, but the installation direction must be carefully considered.

In addition, tires can be categorized by tire pressure into high-pressure tires, low-pressure tires, and ultra-low-pressure tires. Passenger cars mostly use low-pressure tires, which offer a balance of comfort and load-bearing capacity.

Based on structure, tires are divided into radial tires and bias-ply tires. Radial tires, due to their advantages of low rolling resistance, good wear resistance, and long lifespan, have largely replaced bias-ply tires as the mainstream in the market.

Tire sidewall markings are crucial for understanding performance, containing core parameters such as specifications, load index, and speed rating. Accurate interpretation is a prerequisite for purchasing and using tires.

Taking "225/55 R18 98V XL M+S" as an example, the meanings of each parameter are as follows: 225 is the tread width (mm); a higher number indicates stronger grip but higher fuel consumption; 55 is the aspect ratio; a lower number indicates better handling but less comfort, and vice versa; R represents radial construction; and 18 is the rim diameter (inches), requiring precise matching. 98 is the load index (corresponding to a maximum load of 750kg per tire), V is the speed rating (corresponding to a maximum speed of 240km/h), and must be matched to the vehicle's requirements; XL is a reinforced tire, suitable for heavier vehicles such as SUVs; M+S is a mud and snow tire, suitable for snowy regions in the north.

In addition, the sidewall also indicates the abrasion index (the higher the value, the stronger the abrasion resistance), traction rating (AA is the best, C is the worst), and temperature rating (A has the best heat dissipation). The production date is marked with four digits (e.g., 2325 represents the 23rd week of 2025). The optimal service life of tires is 5 years from the date of production; after this period, even if there is no wear, they should be replaced to avoid safety risks caused by rubber aging.

When purchasing tires, three principles should be followed: "suitability first, scenario matching, and quality assurance." Regarding suitability, the tires must strictly match the original factory specifications (tread width, aspect ratio, load index, speed rating, etc.) and be consistent with the vehicle's instruction manual; they should not be arbitrarily changed.

In terms of scenario matching, family commuter sedans should prioritize quiet and comfortable symmetrical/asymmetrical tread patterns; high-grip, high-rigidity sports tires are commonly used for highways/mountain roads; urban SUVs should choose dedicated tires that balance comfort and light off-road capability, while AT/MT off-road tires are recommended for off-road driving.

Brand selection can be tailored to specific needs; first-tier brands emphasize comfort or handling, while domestic brands offer better value for money. It is essential to purchase tires from reputable channels, avoiding retreaded and grey market tires, and not choosing tires that have been in stock for more than 3 years; owners of new energy vehicles should prioritize dedicated tires with low rolling resistance and quiet operation, suitable for the vehicle's high torque and weight.

Scientific maintenance is key to extending tire life and ensuring safety, covering five core dimensions: First, precise pressure control: Check tire pressure (including the spare tire) monthly when the tires are cool, referring to the vehicle's labeled standard value. In winter, a slight adjustment of 0.1-0.2 bar is acceptable, while in summer, strictly adhere to the standard value to prevent high-temperature risks.

Second, regular tire rotation: Perform rotation every 5000-8000 kilometers, alternating between front-wheel drive and rear-wheel drive, and swapping the front and rear of four-wheel drive tires. Dynamic balancing is required after rotation. Third, drive safely and avoid overloading, frequent sudden acceleration and deceleration, and high-speed cornering. Slow down on uneven roads and near curbs.

Fourth, conduct daily inspections and remove foreign objects. Regularly check the tire's appearance and replace it immediately if bulges, cracks, or other damage are found. Clean foreign objects from the tire tread grooves promptly.

Fifth, take precautions in special scenarios. For long-term parking, choose a flat, dry location and move the tires regularly. Clean tires regularly on coastal/saline-alkali roads. Replace tires with non-winter tires promptly after winter. Furthermore, tires with a tread depth less than 1.6mm should be replaced immediately to avoid the risk of skidding in rainy weather.