Drum brakes use a brake transmission mechanism to press the brake shoes onto the inner side of the brake drum, generating braking force that slows down the wheels or stops them within a short distance as needed to ensure driving safety and ensure reliable parking without automatic slippage.

Drum brakes are inexpensive and conform to traditional designs. During the braking process of a four-wheel sedan, due to the effect of inertia, the load on the front wheels usually accounts for 70% -80% of the total load of the car. The braking force of the front wheels is greater than that of the rear wheels, and the rear wheels play an auxiliary braking role. Therefore, in order to save costs, sedan manufacturers adopt a front disc and rear drum braking method. However, for heavy-duty vehicles, due to the generally lower speed and higher durability of brake shoes compared to disc brakes, many heavy-duty vehicles still use four-wheel drum designs to this day.