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					PATH: Brakes > Rear Drum Brakes > Brake Shoes > Adjustment
 Adjustment

   Animations and Tech Tips




       Click to view: The starwheel adjuster
                1. Raise the vehicle and support it with jack stands.
                2. Remove the adjusting hole cover from the rear of the backing
                    plate.
                3. Insert a brake adjustment tool into the adjusting hole and turn the
                    starwheel on the adjusting screw while turning the wheel by hand.
                    Keep turning the starwheel until the wheel can just be turned by
                    hand.
                4. On vehicles equipped with duo-servo drum brakes, back off the
                    adjusting screw 33 times.
                5. On vehicles equipped with leading/trailing drum brakes, back off
                    the adjusting screw 20 times.
                6. Perform this procedure at both wheels.
                7. Install the adjusting hole cover and check the parking brake
                    adjustment.
                8. Lower the vehicle.
                9. Make the final adjustment by driving the vehicle very slowly in
                    reverse and pumping the brakes until the self-adjusting
                    mechanisms adjust to the proper level and the brake pedal reaches
                    satisfactory height.
                10. Road test the vehicle.

PATH: Brakes > Rear Drum Brakes > Brake Shoes > Removal &
Installation > Duo-Servo Brakes
     Duo-Servo Brakes

                                          CAUTION




      Dust and dirt accumulating on brake parts during normal use may contain
      asbestos fibers from production or aftermarket brake linings. Breathing
      excessive concentrations of asbestos fibers can cause serious bodily harm.
      Exercise care when servicing brake parts. Do not sand or grind brake lining
      unless equipment used is designed to contain the dust residue. Do not clean
      brake parts with compressed air or by dry brushing. Cleaning should be done
      by dampening the brake components with a fine mist of water, then wiping the
      brake components clean with a dampened cloth. Dispose of cloth and all
      residue containing asbestos fibers in an impermeable container with the
appropriate label. Follow practices prescribed by the Occupational Safety and
Health Administration (OSHA) and the Environmental Protection Agency
(EPA) for the handling, processing, and disposing of dust or debris that may
contain asbestos fibers.

         1.  Raise the vehicle and support it safely.
         2.  Remove the tire and wheel assembly.
         3.  Remove the brake drums.
         4.  Using a brake tool, remove the shoe return springs.
         5.  Remove the shoe guide.
         6.  Remove the hold-down springs and pins.
         7.  Remove the actuator lever and pivot.
         8.  Remove the lever return spring.
         9.  Remove the actuator link, parking brake strut, spring retaining
             ring.
         10. Remove the parking brake lever and washer.
         11. Remove the shoe assemblies.
         12. Remove the adjuster screw and spring from the shoe assembly.




              Exploded view of the rear drum brake assembly—G-
                   Series Van, Savana with Duo-Servo type
                              Click to Enlarge
To install:
              1. Use a brake cleaning fluid to remove dirt from the brake drum.
                  Check the drums for scoring, cracks and for out-of-round; service
                  the drums as necessary.
              2. Check the wheel cylinders by carefully pulling the lower edges of
                  the wheel cylinder boots away from the cylinders. If there is
                  excessive leakage, the inside of the cylinder will drip fluid; repair
                  or replace as necessary.
              3. Check the flange plate, which is located around the axle, for
                  leakage of differential lubricant.
              4. Lightly lubricate the parking brake cable, parking brake lever
                  where it enters the shoe and the backing plate-to-shoe contact
                  points. Use high temperature, waterproof, grease or special brake
                  lube.
              5. Install the parking brake lever into the secondary shoe with the
                  attaching bolt, spring washer, lockwasher, and nut. It is important
                  that the lever move freely before the shoe is attached. Move the
                  assembly and check for proper action.
              6. Lubricate the adjusting screw and make sure it works freely.
              7. Connect the adjuster screw and spring to the bottom portion of
                  both shoes. Ensure the spring does not interfere with the adjuster
                  rotation when installed. The primary (smaller shoe pad area) to
                  the front and secondary shoe (larger shoe pad area) to the rear of
                  the vehicle.
              8. Install the shoe assembly. Ensuring the shoe webs are positioned
                  correctly against the wheel cylinder.
              9. Install the parking brake cable.
              10. Secure the primary shoes with the hold-down pin and spring.
              11. Install the parking brake strut and the strut spring.
              12. Install the actuator lever and pivot, securing the assembly with the
                  hold-down pin and spring. Install the actuator link and spring.
              13. Install the return springs.
              14. Check the operation of the self-adjusting mechanism by moving
                  the actuating lever by hand.
              15. Adjust the brakes and install the drum.
              16. Adjust the parking brake.
              17. Install the tire and wheel assembly.
              18. Lower the vehicle.

PATH: Brakes > Rear Drum Brakes > Brake Shoes > Removal &
Installation > Leading/Trailing Brakes
    Leading/Trailing Brakes
                                    CAUTION




Dust and dirt accumulating on brake parts during normal use may contain
asbestos fibers from production or aftermarket brake linings. Breathing
excessive concentrations of asbestos fibers can cause serious bodily harm.
Exercise care when servicing brake parts. Do not sand or grind brake lining
unless equipment used is designed to contain the dust residue. Do not clean
brake parts with compressed air or by dry brushing. Cleaning should be done
by dampening the brake components with a fine mist of water, then wiping the
brake components clean with a dampened cloth. Dispose of cloth and all
residue containing asbestos fibers in an impermeable container with the
appropriate label. Follow practices prescribed by the Occupational Safety and
Health Administration (OSHA) and the Environmental Protection Agency
(EPA) for the handling, processing, and disposing of dust or debris that may
contain asbestos fibers.

         1.  Raise the vehicle and support it safely.
         2.  Remove the tire and wheel assembly.
         3.  Remove the brake drums.
         4.  Raise the lever arm of the actuator until the upper end is clear of
             the slot in the adjuster screw.
         5. Slide the actuator off the adjuster pin. Disconnect the actuator
             spring from the shoe.
         6. Remove the hold-down spring assemblies and pins.
         7. Pull the bottom ends of the shoes apart and lift the lower return
             spring over the anchor plate. Allow the shoe ends to come
             together and remove the spring.
         8. Remove the shoe assembly, along with the upper return spring
             and the adjusting screw assembly.
         9. Remove the upper return spring and the adjusting screw assembly
             from the shoes.
         10. Remove the retaining ring, pin, spring washer, and parking brake
             lever.
             Exploded view of the rear drum brake assembly—G-
               Series Van, Savana with Leading/Trailing type
                               Click to Enlarge
To install:
         1. Clean adjuster wheel and the backing plates with a suitable
             cleaner. Lubricate the backing plate contact points, levers and
             adjuster with a suitable lubricant.
         2. Assemble the parking lever, spring washer (concave side facing
             the brake lever), pin, and retaining ring onto the rearward shoe.
         3. Install the adjuster pin in the forward shoe with the pin projecting
             0.276 in. (7mm) from the side of the shoe web where the adjuster
             actuator is installed.
         4. With the brake shoes resting on a flat surface (the shoe with the
             parking lever to the rear of the vehicle), install the upper return
             spring.
         5. Install the adjuster screw assembly with the spring clip facing the
             backing plate.
         6. Place the shoes in position on the backing plate. Do not place the
             lower shoe webs under the anchor plate.
         7. Install the lower return spring, spread the bottom of the shoes and
             position the shoe against the backing plate.
         8. Install the hold-down pins and spring assemblies.
         9. Install the adjuster actuator over the end of the adjuster pin so the
             top leg engages the notch in the adjuster screw.
         10. Install the actuator spring, being careful not to over-stretch it
             more than 3.27 in. (83mm).
         11. Install the parking brake cable to the lever.
         12. Adjust the parking brake if the shoes will not totally retract.
13. Install the drum, tire and wheel assembly. Adjust the rear brakes
    and lower the vehicle.

				
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