Twin Piston Disc Brake Caliper
CALIPER - FRONT TWIN PISTON DISC BRAKEREMOVAL
AWD
NOTE: Before proceeding, Refer to Service Precautions.
1. Disconnect and isolate battery negative cable (2) from battery post.
2. Using a brake pedal holding tool, depress brake pedal past its first inch of travel and hold it in this position. Holding pedal in this position will isolate master cylinder from hydraulic brake system and will not allow brake fluid to drain out of brake fluid reservoir while brake lines are open.
3. Raise and support vehicle.
4. Remove wheel mounting nuts (3), then tire and wheel assembly (1).
5. Remove banjo bolt (3) connecting flexible brake hose (1) to caliper (4). There are two sealing washers (2) (one each side of hose fitting) that will come off when bolt is removed. Discard these washers; install NEW washers on installation.
6. While holding guide pins from turning, remove caliper guide pin bolts (1).
7. Remove brake caliper (3) from brake adapter (2) and pads.
RWD
NOTE: Before proceeding, Refer to Service Precautions.
1. Disconnect and isolate battery negative cable (2) from battery post.
2. Using a brake pedal holding tool, depress brake pedal past its first inch of travel and hold it in this position. Holding pedal in this position will isolate master cylinder from hydraulic brake system and will not allow brake fluid to drain out of brake fluid reservoir while brake lines are open.
3. Raise and support vehicle.
4. Remove wheel mounting nuts (3), then tire and wheel assembly (1).
5. Remove banjo bolt (6) connecting flexible brake hose (1) to caliper (5). There are two sealing washers (7) (one each side of hose fitting) that will come off when bolt is removed. Discard these washers; install NEW washers on installation.
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6. While holding guide pins from turning, remove caliper guide pin bolts (2).
7. Remove brake caliper (1) from brake adapter (3) and pads.
DISASSEMBLY
NOTE: Before disassembling the brake caliper, clean and inspect it.
WARNING: Under no condition should high pressure air ever be used to remove a piston from a caliper bore. Personal injury could result from such practice.
1. Drain brake fluid from caliper.
CAUTION: Do not use excessive force when clamping caliper (2) in vise. Caliper housing is made of aluminum. Excessive vise pressure will cause bore distortion.
2. Mount caliper (2) in vise equipped with protective jaws.
3. C-clamp (1) a block of wood (3) over one piston.
4. Take another block of wood and pad it with one inch thickness of shop towels. Padded block should be sized to allow piston to push out of bore far enough to be removed by hand after being loosened by air pressure, yet large enough to keep piston from coming completely out.
5. Place the padded block of wood (1) in outboard shoe side of caliper (2) in front of exposed piston (3). This will cushion and protect caliper piston during removal.
WARNING: Do not place face or hands near caliper and piston if using compressed air to remove piston. Do not use high pressure.
WARNING: Never attempt to catch piston as it leaves bore. This could result in personal injury.
CAUTION: Do not blow piston out of bore with sustained air pressure. This could result in a cracked piston. Use only short spurts of air.
6. Apply short spurts of low pressure air with a rubber tipped blow gun through caliper brake hose port. Use only enough air pressure to ease piston out of bore.
7. Remove piston from caliper (2).
8. Remove C-clamp and block of wood.
9. C-clamp (1) the block of wood (3) over dust boot of first piston removed. This will seal empty piston bore.
10. Move padded piece of wood (1) in front of piston (2) yet to be removed.
11. Remove second piston using same procedure with short spurts of low pressure air.
12. Remove C-clamp and block of wood from caliper.
13. Remove piston dust boots (1) (over each bore) with an appropriate pry tool (2). Use care not to damage aluminum housing.
CAUTION: Use an appropriate tool (1) to remove piston seals (2) to avoid scratching piston bore. Do not use a screwdriver or other metal tool to remove seals.
14. Using a soft tool such as a plastic trim stick (1), remove piston seals (2) from caliper bores.
15. Remove caliper bleeder screw (2) from caliper housing (1).
16. Clean piston bore and drilled passage ways with alcohol or a suitable solvent. Wipe it dry using only a lint-free cloth.
17. Inspect both piston and bore for scoring or pitting.
NOTE: It is not recommended to hone caliper bore. The anodized coating would be compromised.
CLEANING
WARNING: 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.
To clean or flush the internal passages of the brake caliper, use fresh brake fluid or Mopar� Non-Chlorinated Brake Parts Cleaner. Never use gasoline, kerosene, alcohol, oil, transmission fluid or any fluid containing mineral oil to clean the caliper. These fluids will damage rubber cups and seals.
INSPECTION
Inspect the disc brake caliper for the following: Cracked or damaged housing Brake fluid leaks in and around boot area Ruptures, brittleness or damage to the piston dust boot
If caliper fails inspection, disassemble and recondition caliper, replacing the seals and dust boots or replace caliper.
ASSEMBLY
CAUTION: Dirt, oil, and solvents can damage caliper seals. Ensure assembly area is clean and dry.
NOTE: Always use new, clean Mopar� DOT 3 Motor Vehicle Brake Fluid when assembling brake caliper.
NOTE: Never use old or used piston seals or boots for assembly.
1. Lubricate caliper pistons, piston seals (1) and piston bores (2) with clean, fresh brake fluid.
2. Install NEW piston seal (1) into groove of each caliper piston bore (2).
NOTE: Make sure seal is fully seated and not twisted in groove.
3. Install NEW boot (1) on each piston (2) and work boot lip into groove at top of piston. Stretch boot rearward straightening boot folds, then move boot forward as necessary until folds snap uniformly into place.
4. Install each piston (1), one at a time, into its caliper piston (2) bore, pressing piston down to bottom of bore using hand-pressure. Using a piece of wood or wooden hammer handle may also suffice as long as piston and boot damage is avoided.
CAUTION: When seating dust boots in following step, use care not to over-install boots or damage will occur. Each boot (2) will bottom in the counterbore before the top of the boot reaches the surface of the caliper. The boot will bottom with approximately 2 mm (1/16 inch) (3) of boot still showing above caliper housing.
5. Seat dust boots (3) in caliper counterbores using Installer (2), Special Tool 9315, with Handle (1), Special Tool C-417 1. Install each dust boot until it bottoms. Do not over-seat dust boot or damage will occur.
6. Install caliper bleeder screw (2) in caliper housing (1). Tighten bleeder screw to 15 Nm (125 inch lbs.) torque.
7. Install caliper on vehicle.
INSTALLATION
AWD
CAUTION: Always inspect brake pads before installing disc brake caliper and replace as necessary.
1. Completely retract caliper pistons back into bores of caliper. Use hand pressure or a C-clamp may also be used to retract pistons, first placing a wood block over piston before installing C-clamp to avoid damaging piston.
CAUTION: Use care when installing caliper onto disc brake adapter to avoid damaging boots on caliper guide pins.
2. Push caliper guide pins into caliper adapter to clear caliper mounting bosses when installing.
3. Slide caliper (3) over brake pads and onto caliper adapter (2).
CAUTION: Extreme caution should be taken not to crossthread caliper guide pin bolts (1) when they are installed.
4. Align caliper mounting holes with guide pins, then install guide pin bolts (1). While holding guide pins from turning, tighten bolts to 60 Nm (44 ft. lbs.) torque.
5. Install banjo bolt (3) attaching brake hose (1) to caliper (4). Install NEW washers (2) on each side of hose fitting as banjo bolt is placed through fitting. Thread banjo bolt into caliper and tighten to 50 Nm (37 ft. lbs.) torque.
6. Install tire and wheel assembly (1). Tighten wheel mounting nuts (3) to 150 Nm (110 ft. lbs.) torque.
7. Lower vehicle.
8. Remove brake pedal holding tool.
9. Connect battery negative cable (2) to battery post. It is important that this is performed properly.
10. Bleed (1) base brake hydraulic system as necessary.
11. Road test vehicle making several stops to wear off any foreign material on brakes and to seat brake shoes.
RWD
CAUTION: Always inspect brake pads before installing disc brake caliper and replace as necessary.
1. Completely retract caliper pistons back into bores of caliper. Use hand pressure or a C-clamp may also be used to retract pistons, first placing a wood block over piston before installing C-clamp to avoid damaging piston.
CAUTION: Use care when installing caliper onto disc brake adapter to avoid damaging boots on caliper guide pins.
2. Push caliper guide pins into caliper adapter to clear caliper mounting bosses when installing.
3. Slide caliper over brake pads and onto caliper adapter (3).
CAUTION: Extreme caution should be taken not to crossthread caliper guide pin bolts (2) when they are installed.
4. Align caliper mounting holes with guide pins, then install guide pin bolts (2). While holding guide pins from turning, tighten bolts to 60 Nm (44 ft. lbs.) torque.
5. Install banjo bolt (6) attaching brake hose (1) to caliper (5). Install NEW washers (7) on each side of hose fitting as banjo bolt is placed through fitting. Thread banjo bolt into caliper and tighten to 50 Nm (37 ft. lbs.) torque.
6. Install tire and wheel assembly (1). Tighten wheel mounting nuts (3) to 150 Nm (110 ft. lbs.) torque.
7. Lower vehicle.
8. Remove brake pedal holding tool.
9. Connect battery negative cable (2) to battery post. It is important that this is performed properly.
10. Bleed (1) base brake hydraulic system as necessary.
11. Road test vehicle making several stops to wear off any foreign material on brakes and to seat brake shoes.