How to Replace the Drum Brakes on a Chevrolet Silveradoby Lee Sallings
The Chevrolet Silverado uses a self-energizing servo, drum brake system common to most rear-wheel-drive General Motors vehicles. This system is composed of a small primary shoe, a larger secondary shoe, self-adjuster mechanism and attaching hardware. Replacing the shoes when worn is a common do-it-yourself project. Take care to install the different-sized shoes in the correct location.
Jack the axle up until the wheel is off the ground, then place a jack stand under the axle for added safety. Remove the lug nuts by turning them counterclockwise with the lug wrench, and lift the wheel off to gain access to the brake system.
Remove the drum from the brake system. It can be stubborn; if so, try hitting the edge of the drum with a sharp blow from a hammer, which will free the drum of any rust that has built up around the axle.
Remove the old shoes by removing the return down springs that attach the shoes to the anchor pin at the top of the assembly. This will allow the self-adjuster and parking brake spreader bar to fall free. Remove the primary and secondary shoes by releasing the hold-down springs attaching them to the backing plate. The secondary shoe is attached to the parking brake lever by a U-shaped clip; remove this clip.
Clean the hardware and backing plate with brake parts cleaner, and let it dry completely. From here on, pay attention to cleanliness. Avoid contaminating the shoes with dirt and grease, which can cause groaning and shudder of the brakes.
Lubricate the contact points, the three raised areas on each side of the backing plate, with brake grease.
Begin installing the new secondary shoe, the longer of the two shoes. It goes on the side of the assembly closest to the rear of the vehicle. Attach the shoe to the parking brake lever, then attach it to the backing plate with a hold-down spring.
Install the primary shoe to the backing plate with a hold-down spring. Make sure both shoes are positioned on the contact points of the backing plate and lined up on the anchor pin.
Install the parking brake spreader bar, self-adjuster cable and return springs. The parking brake spreader goes between the two shoes, at the top, and attaches the primary shoe to the parking brake lever. The loop on the adjuster cable slips over the anchor pin and is held in place by the return springs.
Install the self-adjuster return spring in the lower holes of the shoes, and slip the self-adjuster into place by spreading the shoes slightly. Install the star wheel side first, then slip the long side into place on the shoe.
Install the drum, and check the brakes for adjustment. Rotate the star wheel until the shoes are adjusted to fit the drum. There should be a slight drag when you rotate the drum. You've attained the proper fit when the wheel rotates about one turn before stopping when you spin it.
Reinstall the wheel by tightening the lug nuts in a star pattern, and lower the car to the ground. Check the tightness of the lug nuts, then test-drive the car.
- Make sure to install the brake shoes in their correct location. The most common cause of drum brake problems after replacement is that the shoes were installed in the wrong position.
- Do not use axle grease to lubricate the contact points on the backing plate; axle grease is too light and will melt off when the brakes are heated from use. Instead, use brake grease.