What Does a Equalizer Bar Do on Drum Brakes?

The equalizer bar interacts with the drum brakes.

A vehicle's braking system has many interacting parts. Specifically, the rear drum brakes and the parking brake are connected, which includes the use of an equalizer bar, for functionality and safety.

Identification

The brake drum is an assembly of enclosed brake shoes that press up against the drum when the brake pedal is depressed, causing friction and subsequent slowing of the vehicle. An equalizer bar is part of the parking brake assembly, stabilizing the two cables that extend from the handle inside the car for activation to their attachment on the rear brakes.

Function

The equalizer bar allows the pressure of the parking brake to be applied to both rear brake drums uniformly if the brakes fail. The parking brake provides a mechanical action, as opposed to the brake drum's hydraulically controlled action, in case of an emergency to slow down the car.

Significance

Without the use of the equalizer bar for the parking brake, the mechanical braking system will not be applied correctly to either side of the car's wheels. In a braking emergency, this mechanism must work for the safety of the driver and passengers.

References

• Auto MD: How to Replace a Parking Brake Cable
• Family Car: A Short Course on Brakes