How to Deal with Rear Wheel Lock-Up on BYD F3?

[AbigailRose]

For a BYD F3 experiencing rear wheel lock-up, you can remove the tire and gently tap the brake drum with a hammer a couple of times to loosen the contact surface between the brake drum and the brake pads. Alternatively, pour 100°C boiling water over the brake pad area and then repeatedly move the vehicle forward and backward about three times. Wheel lock-up occurs when the brake clamps the tire tightly, preventing any relative movement between the tire and the brake, causing the tire to skid on the ground. In vehicles without ABS, forcefully pressing the brake pedal while driving causes the wheel speed to drop rapidly. If the braking force exceeds the friction between the tire and the ground, the wheel locks up completely, reducing the friction between the tire and the ground. Causes of Wheel Lock-Up: 1. Sticking or failure of the master cylinder piston cup to return. This is usually caused by water or other contaminants entering the brake system or failure to clean the system before changing to a different brand of brake fluid, causing the master cylinder piston cup to swell. 2. Poor fit between the master cylinder piston cup and the master cylinder bore. This issue often arises during the development phase, where excessive interference between the piston cup and the cylinder bore leads to the piston cup failing to return or returning poorly after braking. 3. Failure of the brake caliper piston to return or return poorly. This can be due to inferior material performance of the square seal or poor dimensional fit among the square seal, caliper bore, and caliper piston, resulting in insufficient return of the square seal and causing wheel drag or even lock-up. 4. Insufficient stiffness of the brake disc. Frequent braking can cause the brake disc to deform under high temperatures due to inadequate stiffness, leading to wheel lock-up during subsequent use.