On many vehicles, drum brakes are an integral part of the braking system. They are typically found at the rear wheels of your vehicle. Drum brakes not only slow and stop your vehicle, but they also function as the parking or emergency brake.
Drum brakes work on the same principle as disc brakes, but when the brakes are applied, hydraulic pressure forces the brake shoes OUT, against the inside of the brake drum, to create the necessary friction required to slow and stop the vehicle. When the pressure is released, return springs pull the shoes back to their original position allowing the wheel to turn freely.
However, springs eventually lose their resiliency, and both brake shoes and drums wear out over time. We recommend inspecting both front and rear brakes regularly: replacing brake shoes when the remaining friction material is measured at 2 mm or less, brake drums when they exceed their maximum diameter, and brake hardware as required.
Our technicians at Olsen's Automotive Repair in Livermore will measure the thickness of the drums every time your brakes are serviced as worn-out drums might not have enough metal left for safe braking. If ignored, brake drums may wear unevenly causing vibration and/or noise. A worn-out brake drum may contribute to premature brake shoe wear, which leads to more frequent shoe replacement and cost of repair.
From a safety standpoint, worn brake drums may dramatically increase the distance required for you to stop, cause the vehicle to pull to one side, or result in loss of control which could cause injury to you and possibly others. Neglecting brake drum maintenance has no environmental impact. Call us at 925-447-4070 or go to our website to schedule an appointment with us!