Brake Systems: Calipers
NOTE:
You are not required to replace or rebuild calipers in axle sets. However, when replacing or rebuilding a caliper due to the conditions that follow, you may suggest servicing, rebuilding, or replacement of the other caliper (on the same axle) for improved performance and preventive maintenance (for example, the part is close to the end of its useful life, replacing the caliper may extend pad life, or contribute to more balanced braking). When installing loaded calipers, it is required that friction material be matched in axle sets for consistent braking characteristics.
| Condition | Code | Procedure |
|---|---|---|
| Bleeder port damaged | A | Require repair or replacement of caliper |
| Bleeder screw broken off in caliper | A | Require repair or replacement of caliper |
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NOTE:
Only required if hydraulic system must be opened.
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| Bleeder screw plugged | A | Require repair or replacement of bleeder screw |
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NOTE:
Only required if hydraulic system must be opened.
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| Bleeder screw seized | A | Require replacement of caliper |
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NOTE:
Seized is defined as a bleeder screw that cannot be removed after a practical attempt at removing. Only required if the hydraulic system must be opened.
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| Casting corroded, affecting structural integrity | A | Require replacement |
| Casting damaged, affecting structural integrity | A | Require replacement |
| Dust boot around caliper piston torn | A | Require replacement of dust boot |
| Leaking | A | Require repair or replacement |
| Mounting pin threads damaged | A | Require repair or replacement of component with damaged threads |
| Mounting pin threads stripped (threads missing) | A | Require repair or replacement of component with stripped threads |
| Mounting pin threads stripped in caliper bracket (threads missing) | A | Require repair or replacement of caliper bracket |
| Mounting pin threads stripped in steering knuckle (threads missing) | A | Require repair or replacement of steering knuckle |
| Parking brake cable support, lever, or return spring bent | A | Require replacement of parts |
| Parking brake cable support, lever, or return spring broken | A | Require replacement of parts |
| Parking brake mechanism in caliper inoperative | A | Require repair or replacement |
| Piston corroded (pitted or peeling chrome plating) | B | Require replacement of piston and rebuilding or replacement of caliper |
| Piston damaged, affecting performance | B | Require replacement of piston and rebuilding or replacement of caliper |
| Piston damaged, not affecting performance | No service suggested or required | |
| Piston finish worn off | B | Require replacement of piston and rebuilding or replacement of caliper |
| Piston sticking | A | Require rebuilding or replacement of caliper |
| Slide mechanism sticking | A | Require repair or replacement of slide mechanism |