See Figures 1 through 8
See Figure 9
An inspection hole is provided in the backing plate of each rear wheel which allows the brakes to be checked without removing the drum. Remove the hole plug and check the lining thickness through the hole. If below minimum, the shoes will need replacement. Always replace the plug after checking, making certain it is properly seated and tight.
It should be obvious that this method doesn't provide a lot of information about how the brakes are wearing since it only shows one part of one shoe, but is a quick and easy first check. The only way to see the friction faces of the shoes is to remove the brake drums. No generalities can be drawn between the left and right side shoes, so both drums must be removed to perform a proper inspection.
With the drums removed:
- Liberally spray the entire brake assembly with an evaporative brake cleaner. Do not use other solvents, compressed air or a dry brush.
- Measure the thickness of the friction surface on each shoe at several different locations. If any measurement is below the minimum thickness, replace all the shoes as a set. Refer to Brake Specifications Chart in this section.
- Check the contact surfaces closely for any signs of scoring, cracking, uneven or tapered wear, discoloration or separation from the backing plate. Anything that looks unusual requires replacement.
- If the shoes are in otherwise good condition except for glazing (a shiny, hard surface), the glaze may be removed by light sanding with emery cloth. Also lightly sand the inside of the drum to de-glaze its surface. Do not attempt to rub out grooves or ridges; this is best done with a resurfacing lathe. After sanding the components wash them thoroughly with aerosol brake cleaner to remove any grit.
REMOVAL & INSTALLATION
See Figures 10 through 14
The brake shoes can be removed and replaced using everyday hand tools, but the use of brake spring tools and assorted specialty tools makes the job much easier. These common brake tools are available at low cost and can greatly reduce working time. Record the location of all brake hardware (spring etc.) before starting this service procedure. Work on one side at a time, so that the other side may be used as guide. Do not apply the brake pedal while the drum is removed
We recommend replacement of the brake shoes in axle sets for added safety and reliability
- Perform the Brake Drum Removal procedure as previously detailed.
- Unhook the shoe tension springs from the shoes with the aid of a brake spring removing tool.
- Remove the brake shoe securing springs.
- Disconnect the parking brake cable at the parking brake shoe lever.
- Withdraw the shoes, complete with the parking brake shoe lever.
- Unfasten the C-clip and remove the adjuster assembly from the shoes. Inspect the shoes for wear and scoring. Have the linings replaced if their thickness is less than minimum specifications (refer to Brake Specifications chart in this section). Check the tension springs to see if they are weak, distorted or rusted.
- Inspect the teeth on the automatic adjuster wheel for chipping or other damage.
Grease the point of the shoe which slides against the backing plate. Do not get grease on the linings
- Attach the parking brake shoe lever and the automatic adjuster lever to the rear side of the shoe.
- Fasten the parking brake cable to the lever on the brake shoe.
- Install the automatic adjuster or strut and fit the tension spring on the adjuster lever.
When assembling the rear shoe and the automatic adjuster, check the clearance between the shoe and the lever using a feeler gauge. Clearance should be 0-0.0138 inch (0-0.35mm); if not within specifications, adjustment can be made by replacing the shim on the adjusting lever shaft. Shims are available in 0.04 inch (1mm) increments from 0.008-0.024 inch (0.2-0.6mm). There is also one measuring 0.035 inch (0.8mm). To replace the shim, remove the C-clip, install a shim of the proper thickness and then install a new C-clip
- Install the securing spring on the rear shoe and then install the securing the spring on the front shoe.
- Hold one end of the tension spring over the rear shoe with the tool used during removal; hook the other end over the front shoe. Install all necessary springs
Be sure that the wheel cylinder boots are not being pinched in the ends of the shoes
- If equipped, test the automatic adjuster by operating the parking brake shoe lever.
- Install the drum and adjust the brakes as previously detailed.