Are the Braking Distances of Large Trucks Long or Short?
3 Answers
The longer, the factors affecting braking distance include the following: 1. Suspension system: It is generally difficult to associate the suspension system with braking distance, but in fact, the suspension system does have an impact on braking distance. During emergency braking, the vehicle's center of gravity shifts forward, compressing the front suspension. If the front suspension lacks sufficient support, it can lead to excessive forward shift of the vehicle's center of gravity, reducing the rear tires' grip and weakening their braking effect, thereby increasing the braking distance. Some vehicles exhibit severe front-end dipping during braking, which is a sign of poor front suspension support. 2. Vehicle weight: The greater the weight of the vehicle, the greater the inertia, making it harder to stop. Therefore, vehicle weight also has a direct impact on braking distance. However, this does not mean that heavier vehicles necessarily have longer braking distances than lighter ones. For example, some performance cars weigh much more than family A-segment cars but have much better braking performance because factors like tires and braking systems must also be considered. The effect of vehicle weight on braking distance mainly manifests in that for the same vehicle, under the same braking system, the greater the load, the longer the braking distance. 3. Tires: Tires are the medium through which the braking system operates. The better the tire grip, the more braking force can be obtained during braking, and the shorter the braking distance can be. For general family cars, the main factor affecting braking distance is tire width—the wider the tire, the larger the contact area, and the greater the braking force. 4. ABS: ABS stands for Anti-lock Braking System, which prevents wheel lock-up, ensuring vehicle control during emergency braking. Research has found that the ground braking force is greatest when the wheel slip ratio is between 15%-20%, providing the best braking effect. Therefore, ABS systems are designed to maintain the slip ratio of nearly locked-up tires within this range to achieve optimal braking performance. Thus, on dry roads, ABS can achieve a shorter braking distance than locked-up tires during emergency braking when tires are about to lock up. Always pay attention while driving.
As a long-time truck driver, I can confidently tell you that the braking distance is much longer compared to passenger cars. This is mainly because the vehicle is too heavy—when I'm hauling cargo weighing tens of tons, the braking system has to work much harder to slow down. For example, driving at 80 km/h on the highway, a passenger car might stop in about 50 meters, but the truck I drive needs over 100 meters. Why? The inertia is too great, and the brake pads are racing against time to create enough friction. I've even encountered a few close calls—on rainy days when the road is slippery, the braking distance becomes even longer, and I almost rear-ended someone. That’s why I’m extra cautious now: braking early, maintaining a following distance of at least 300 meters, avoiding sudden stops, and regularly inspecting the braking system—like checking for air brake leaks to avoid failures in critical moments. Safety comes first—don’t take this lightly.
From the perspective of vehicle mechanics, large trucks indeed have longer braking distances. Simply put, it's Newton's laws at play: greater mass means stronger inertia. A passenger car might stop with just a few disc brake applications, but trucks use air brake systems where pressure transmission is slower, and tire friction coefficients are lower, especially when fully loaded. Based on my previous research, under the same speed conditions, a truck's braking distance can be 1.5 times or even longer than that of a sedan. However, this can be mitigated through technology—such as ensuring proper tire pressure, using high-performance brake pads, or installing ABS anti-lock braking systems. But generally speaking, it's crucial to maintain a larger safety margin while driving and avoid tailgating. Inexperienced drivers often misjudge these factors, and accidents can lead to irreversible regret.
