See Figures 1 and 2
Support the vans on jackstands and remove the wheels. Look in at the ends of the caliper to check the lining thickness of the outer pad. Look through the inspection hole in the top of the caliper to check the thickness of the inner pad. Minimum acceptable pad thickness is 1 / 32 in. (0.8mm) from the rivet heads on original equipment riveted linings and 1 / 2 in. (13mm) lining thickness on bonded linings.
The manufacturer's specifications may not agree with your state inspection law.
All original equipment pads are the riveted type; unless you want to remove the pads to measure the actual thickness from the rivet heads, you will have to make the limit for visual inspection 1 / 16 in. (1.6mm) or more. The same applies if you don't know what kind of lining you have. Original equipment pads and GM replacement pads have an integral wear sensor. This is a spring steel tab on the rear edge of the inner pad which produces a squeal by rubbing against the rotor to warn that the pads have reached their wear limit. They do not squeal when the brakes are applied.
The squeal will eventually stop if worn pads aren't replaced. Should this happen, replace the pads immediately to prevent expensive rotor (disc) damage.
REMOVAL & INSTALLATION
See Figures 3, 4, 5, 6, 7, 8 and 9
- Remove approximately 1 / 3 of the brake fluid from the master cylinder. Discard the used brake fluid.
- Jack up your vehicle and support it with jackstands.
- Push the piston back into its bore. This can be done by suing a C-clamp.
- Remove the bolt at the caliper support key. Use a brass drift pin to remove the key and spring.
- Rotate the caliper up and forward from the bottom and lift it off the caliper support.
- Tie the caliper out of the way with a piece of wire. Be careful not to damage the brake line.
- Remove the inner shoe from the caliper support. Discard the inner shoe clip.
- Remove the outer shoe from the caliper.
- Lubricate the caliper support and support spring, with silicone.
- Install a NEW inboard shoe clip on the shoe.
- Install the lower end of the inboard shoe into the groove provided in the support. Slide the upper end of the shoe into position. Be sure the clip remains in position.
- Position the outboard shoe in the caliper with the ears at the top of the shoe over the caliper ears and the tab at the bottom of the shoe engaged in the caliper cutout. If assembly is difficult, a C-clamp may be used. Be careful not to mark the lining.
- Position the caliper over the brake disc, top edge first. Rotate the caliper downward onto the support.
- Place the spring over the caliper support key, install the assembly between the support and lower caliper groove. Tap into place until the key retaining screw can be installed.
- Install the screw and tighten to 15 ft. lbs. (20 Nm). The boss must fit fully into the circular cutout in the key.
- Install the wheel and add brake fluid as necessary.