Brakes are a vehicle's most important part. They probably have the toughest job: stopping thousands of pounds of metal, plastic, flesh and bone that can travel at high speeds. Because your brakes are responsible for your safety and the safety of others, they should be visually checked every time the car's wheels are taken off for tire rotation or other service. More important, they should be checked if they exhibit any of the following symptoms:
- The car pulls to one side during braking.
- Squeaks, grinding or other noises are heard when the brakes are applied.
- The pedal pushes farther toward the floorboard than normal.
- The pedal pulsates during normal braking.
- Evidence of brake fluid appears inside the tire/wheel or on the ground.
New Shoes
Drum brakes were standard at all four corners on most vehicles until the early 1970s. In a nutshell, this system functions by the brake pedal sending fluid to the wheel cylinders, which push brake shoes outward until they contact the drums. The friction between the shoes and drums slows and eventually stops the vehicle. This friction also wears down the linings on both the drum and shoes over time, which is why brake inspection and replacement is the most vital part of routine maintenance.
Begin your brake inspection by jacking up the vehicle, securing it on jackstands and removing the tire/wheel. Play it safe and wear a filtering mask because brake dust may contain asbestos.
Scribe the drum and hub with chalk so that the drum can be reinstalled in the same position. When servicing rear brakes, make sure that the emergency brake isn't set – then remove the drums. If they don't come off easily, spray penetrating oil around the hub area and tap around the drum with a hammer. Still frozen? Retract the brake shoes by accessing the adjuster's star wheel. Knock out the access plug in the brake's backing plate with a hammer and chisel if necessary. Then use a small screwdriver to turn the star wheel until the shoes retract far enough to remove the drum.
At this point, look for leaky brake fluid. Spewing brake cylinders should be rebuilt or replaced, which involves disconnecting the brake line and bleeding the brakes after the new cylinder is installed. Then spray all components with brake cleaner; never use petroleum-based solvents.
Inspect the shoe lining. It should have more than 1/16-inch of “meat” beyond the shoe's outer surface or rivets. Shoes that are worn to this point or are cracked or glazed should be replaced. Also check the inside of the brake drums for cracks, scratches and discolored areas. Many parts stores will “turn” drums on a lathe for free or a minimal charge with the purchase of new shoes. This process removes high spots and slight imperfections on the drum's friction surface.
Different shoe compositions are available for different driving styles. They range from organic to semi-metallic to carbon fiber. The pros and cons of each is a story unto itself.
The accompanying photos give an overview of how to remove and replace brake shoes. For demonstration purposes, a rear re-shoe was chosen to show how the emergency brake hardware attaches. Specialized brake-tool kits are available to expedite the job, but we show how to do it with basic hand tools. Refer to a service manual for any specific procedures for your vehicle.
Step 1 If the drum won't pull off, use penetrating oil, a hammer, or retract the shoes by accessing the adjuster through the backing plate.
Step 2 Inspect all brake parts for signs of wear and fluid leakage, then spray everything with brake-parts cleaner. Many parts stores will “turn” drums with the purchase of new shoes. These drums had previously been turned, and the remaining lining thickness wasn't up to spec.
Step 3 Leave one side assembled for reference while working on the other. Begin by removing the return springs from the actuator. A special tool is available to make this step easier.
Step 4 Unhook the actuator link from the anchor pin and secondary (rearward) shoe.
Step 5 Remove the hold-down spring assemblies. A special tool is also made for this step.
Step 6 Remove the actuator/springs assembly.
Step 7 Remove the adjuster, noting which direction it faces, and then the parking brake strut (above the hub and under the wheel cylinder). Clean the adjuster, then lubricate its threads with high-temp grease.
Step 8 Remove the old shoes, unclipping one of them from the brake actuator if necessary.
Step 9 These shoes didn't wear evenly. A frozen adjuster screw allowed only one shoe (right) to actually make contact with the drum.
Step 10 Clean the backing plate with brake-parts cleaner, smooth the shoe-contact points with emery cloth, then lube these areas with high-temp grease.
Step 11 Reverse the disassembly process to install the new shoes, taking care to keep the lining surfaces clean.
Step 12 This job included new drums. The shoes were retracted with the adjuster screw so that the drum would slide on easily.
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