What Would Cause Brakes to Lock Up on a Car?by Richard Manfredi
When a car's brakes lock up when stopping, it creates an unsafe situation. A car with locked up brakes is unstable and difficult to steer, not letting a driver avoid road hazards while stopping quickly.
Tires can lock up during braking when a person attempts to stop suddenly on wet or slippery road or slams on the brakes instead of braking gradually. This causes an inability to steer or stop as quickly as possible, along with burning a flat spot on the tires from the friction of one patch of rubber hitting the road.
An anti-lock braking system adjusts the brake fluid pressure to stop certain tires from locking up. In cars without an anti-lock braking system, the driver must pump the gas pedal manually in order to prevent tires from locking up.
Tires can lock up during braking even on cars with anti-lock braking systems. Some heavier vehicles, such as vans, pickup trucks and SUVs only have anti-lock braking systems in their rear wheels. These systems will help cars to avoid spinning out, but front wheels can still lock up and cause a loss of steering.