Which type of brake system is commonly used in semis?

The air-operated version of ABS (Anti-lock Braking System) is the common choice in semi-trucks primarily because of the vehicle's size and weight requirements. In heavy-duty vehicles like semis, air brake systems provide the necessary stopping power and reliability needed for safe operation. These systems utilize compressed air to apply the brakes, allowing for a more effective and consistent braking performance, especially under load or in demanding driving conditions.

Moreover, the integration of ABS technology enhances safety by preventing wheel lock-up during hard braking, maintaining traction and control over the vehicle. This is particularly important in commercial vehicles, where stopping distance can be significantly increased due to their mass.

While hydraulic and drum brake systems can be found in various applications, they are less suitable for the demands of semi-trucks compared to air brake systems with ABS functionality. Mechanical brake systems are also not ideal for such heavy vehicles, as they do not provide the efficiency or reliability required in this context.