How to Determine When Drum Brakes Need Replacement?

[DelEdward]

Methods to determine drum brake replacement are: 1. For vehicles with frequent brake usage, it is recommended to consider replacing drum brakes after reaching 80,000 kilometers. 2. For vehicles with infrequent brake usage, it is recommended to consider replacing drum brakes after reaching 100,000 kilometers. 3. If squeaking sounds are heard when applying the brakes, immediately take the vehicle to a service center to inspect the braking system and replace the drum brakes. The working principle of drum brakes is: 1. They utilize stationary brake shoes inside the brake drum to create friction against the rotating drum attached to the wheel, thereby reducing wheel rotation speed. 2. Their components include: brake backing plate, wheel cylinder, brake shoes, related linkages, springs, pins, and brake drum.

[MacCayden]

Actually, I've been driving old cars for many years and am particularly sensitive to the condition of drum brakes. If you feel the brake pedal getting softer while driving and the car doesn't stop well, you need to be careful. Once when going around a corner, I noticed a burnt smell coming from the wheels, and upon checking, the drum brake pads were smoking. It's best to inspect them regularly yourself—just remove the tires to see inside the drum brakes. If the brake pads are worn down to the limit mark (usually around 3mm left), or if there's oil stains, cracks, or the metal backing plate is exposed, they must be replaced. If the brake drum has obvious scratches or feels rough to the touch, it should also be replaced. I remember one rainy day when the brakes squeaked, and upon disassembly, I found the springs were rusted and stuck. Don't wait for a brake failure to address the issue—make sure the mechanic checks this thoroughly during every maintenance session.

[LaRachel]

Inspecting drum brakes mainly involves three steps: listening, looking, and touching. First, listen for abnormal sounds: a 'rustling' metal friction noise when lightly pressing the brakes indicates excessive wear; if there's continuous friction noise even with the handbrake released, the return spring might be faulty. Then, observe the condition. If experienced, peek through the inspection hole—if the brake lining thickness is less than one-third of the original, it's time for replacement. After washing the car, check for oil stains leaking around the wheel hub. Finally, touch for temperature. After a short drive, quickly touch the wheel hub with the back of your hand. If one wheel is noticeably hotter, it's likely due to poor drum brake return. Remember, last time during maintenance, a leaking wheel cylinder was found, directly causing uneven braking force on both sides, making the car pull to one side.

[DiAnthony]

As an owner who frequently drives on mountain roads, I judge drum brakes based on two key indicators. Brake shoe thickness: New shoes are around 12mm, and if measurements show less than 6mm, replace them immediately. Brake drum inner diameter: The diameter of a new drum is marked on its surface; if caliper measurements exceed 2mm beyond this, it needs replacement. Once, when fully loaded and braking downhill, the car shook—upon inspection, the brake drum was found to be worn and deformed. The most noticeable daily signal is when the brake pedal travel becomes longer, requiring deeper presses to be effective. For older cars, pay special attention to brake fluid; if it's cloudy, black, or the level has dropped, it affects drum brake efficiency. Now, during every maintenance session, I make sure the mechanic measures these two data points—it's more reliable than listening for sounds.