Brake Caliper Rebuild - Rear

Complete rebuild of rear brake calipers including disassembly, cleaning, inspection, seal replacement, piston installation, and bleeding on a 2007 Ram 3500 4WD with the 5.9L Cummins diesel engine.

Warnings

Tools required

Parts

• Rear brake caliper rebuild kit (both sides) × 2 — Use OEM Mopar or equivalent containing pistons, seals, dust boots, and hardware
• Brake caliper slide pin boots and hardware kit × 2 — Use OEM specification
• Brake fluid DOT 3 × 2 — Use OEM specification

Fluids

• DOT 3 brake fluid — 1.5 qt

Preparation

1. Park vehicle on level, solid surface and engage parking brake
2. Chock front wheels securely in both directions
3. Loosen rear wheel lug nuts while vehicle is on ground (1/2 turn)
4. Lift rear of vehicle using floor jack at rear differential or frame lift points
5. Support vehicle on jack stands placed under frame rails, ensuring stands are rated for vehicle weight
6. Remove rear wheels completely
7. Place brake fluid catch pan under work area
8. Verify you have complete caliper rebuild kits for both sides before beginning disassembly
9. Have at least 2 quarts of fresh DOT 3 brake fluid available from sealed containers
10. Clean exterior of brake calipers and surrounding area with brake parts cleaner to prevent contamination during disassembly

Procedure

1. 1

   Remove rear brake calipers
   Using a flare nut wrench, carefully loosen the brake line fitting at the caliper (do not remove completely yet). Remove caliper slide pin bolts and lift caliper off rotor. Now completely remove brake line from caliper and immediately plug or cap the line to minimize fluid loss. Support caliper on clean work surface. Repeat for opposite side. Note: The 2007 Ram 3500 rear calipers use a threaded inverted-flare brake line fitting; there are no banjo bolts on the rear calipers.
2. 2

   Disassemble calipers - remove pistons
   Working on one caliper at a time on clean work surface, remove dust boot retaining ring if present. Carefully pry out dust boot. Use compressed air applied to brake fluid inlet port to push piston out of bore - cover piston area with shop towel and apply air gradually to prevent piston from ejecting forcefully. If compressed air is unavailable, use a wooden block and gradually push piston out by hand while twisting. Remove piston and set aside for inspection.
3. 3

   Remove old seals and inspect caliper bore
   Use seal pick tool to carefully remove the piston seal from the groove inside the caliper bore - work gently to avoid scratching the bore. Remove all old seal material completely. Thoroughly clean caliper bore with brake parts cleaner and lint-free cloth. Inspect bore for scoring, pitting, corrosion, or any damage. Minor surface staining is acceptable, but any scratches, grooves, or corrosion deeper than 0.002 inches requires caliper replacement. The bore must be perfectly smooth for proper seal function.
   ⚠Do not use metal tools to clean the caliper bore. Metal contact will damage the precision-machined surface and cause seal failure. Use only plastic picks and soft brushes.
4. 4

   Inspect pistons and caliper body
   Examine each piston for scoring, pitting, chrome plating damage, or corrosion. Any damage to piston surface requires piston replacement. Clean pistons thoroughly with brake parts cleaner. Inspect caliper body casting for cracks, especially around mounting ears and bleed screw boss. Check that bleeder screw threads are not stripped and bleeder valve operates freely (spray with penetrating oil if stuck, do not force). Inspect slide pin bores in caliper bracket for wear or damage.
5. 5

   Clean and prepare components
   Thoroughly clean all caliper components with brake parts cleaner and allow to air dry. Use brass wire brush on caliper body exterior if needed to remove corrosion (avoid bore area). Clean caliper mounting bracket and slide pins with brake cleaner. Blow out all passages with compressed air if available. Ensure bleeder screw passages are clear. All components must be completely clean and dry before assembly - any contamination will cause premature seal failure.
6. 6

   Install new piston seals
   Remove new piston seal from rebuild kit and coat thoroughly with fresh DOT 3 brake fluid. Working carefully to avoid twisting or rolling the seal, install it into the groove in the caliper bore using only your fingers - never use tools to install the seal. Ensure seal is seated evenly in the groove around entire circumference with no twists or folds. The seal must sit flat in the bottom of the groove.
7. 7

   Install pistons
   Coat new or cleaned piston generously with fresh DOT 3 brake fluid, including the sealing surface. Coat inside of new dust boot with brake fluid. Position dust boot on piston according to kit instructions (some install before insertion, others after). Carefully align piston with caliper bore opening and push piston squarely into bore by hand, using a twisting motion to help piston pass the seal. Push piston in until it bottoms in the bore or reaches specified depth per rebuild kit instructions. Install dust boot into caliper body groove and secure with retaining ring if equipped.
   ⚠Do not cock or tilt piston during installation as this will damage the seal. Piston must enter bore perfectly square and straight. If resistance is felt, remove piston and check for seal twisting or debris.
8. 8

   Service caliper slide pins and brackets
   Remove slide pins from caliper brackets. Clean pins and bores thoroughly with brake cleaner. Inspect pin surfaces for scoring, corrosion, or wear. Check slide pin boots for tears or damage - replace if compromised. Apply thin coat of high-temperature silicone brake grease (supplied in kit or use synthetic caliper lube) to slide pins. Install new boots if provided in kit. Reinstall slide pins into brackets ensuring smooth movement through full range of travel.
9. 9

   Reinstall calipers on vehicle
   Position caliper bracket on rotor mounting area and install bracket bolts if removed. Position caliper over rotor and brake pads (ensure pads are in good condition, replace if needed). Install and tighten caliper slide pin bolts per manufacturer specification (verify the exact torque in the factory service manual for the 2007 Ram 3500 rear caliper before final tightening). Connect the threaded inverted-flare brake line fitting to the caliper, hand-thread first to avoid cross-threading, then carefully torque per specification (verify against the factory service manual, typically around 12-15 ft-lb - do not overtighten).
   ⚠Brake line fittings are easily cross-threaded or over-torqued. Thread fittings by hand first to ensure proper thread engagement before using any tools. Stripped caliper body threads require caliper replacement.
10. 10

    Bleed rear brake system - initial bleeding
    Fill master cylinder reservoir with fresh DOT 3 brake fluid to MAX line. Starting with the caliper furthest from master cylinder (typically passenger rear), attach clear bleeder hose to bleeder screw and submerge other end in container with clean brake fluid. Open bleeder screw 1/2 turn. Have helper slowly depress brake pedal to floor and hold. Close bleeder screw, then have helper release pedal. Repeat process until fluid flows without air bubbles (typically 10-15 pumps). Keep master cylinder reservoir filled throughout process.
    ⚠️Never allow master cylinder reservoir to run dry during bleeding. This will introduce air into ABS system requiring dealer-level scan tool to bleed properly.
11. 11

    Complete brake bleeding sequence
    After bleeding passenger rear caliper until bubble-free, move to driver rear caliper and repeat bleeding process. Then bleed passenger front and finally driver front following same procedure. After bleeding all four wheels, return to rear calipers and bleed each one additional time to ensure all air is purged. Top off master cylinder to MAX line with fresh DOT 3 brake fluid. Check that brake pedal is firm - if pedal is soft or spongy, repeat bleeding process.
12. 12

    Leak check and pedal verification
    With vehicle still raised on jack stands, have helper apply firm brake pedal pressure and hold for 30 seconds while you inspect all brake line connections, caliper bleeder screws, and caliper piston seals for any signs of fluid leakage. Check that brake fluid level in reservoir is at MAX line and cap is secure. Pump brake pedal several times and verify firm, consistent pedal feel. Pedal should not slowly sink to floor when held under pressure.
13. 13

    Reinstall wheels and final torque
    Clean wheel mounting surfaces on hub and wheel. Install rear wheels and hand-tighten lug nuts in star pattern. Lower vehicle until wheels just contact ground but vehicle weight is still on jack stands. Torque lug nuts to specification in star pattern (verify the exact lug nut torque in the factory service manual for the 2007 Ram 3500 — values are typically around 145 ft-lb but depend on stud size and single vs. dual rear wheel configuration). Fully lower vehicle and remove jack stands. Torque lug nuts again in star pattern to verify proper torque after vehicle weight is fully on wheels.

Reassembly

1. Double-check that all caliper slide pin bolts are properly torqued
2. Verify brake line connections are secure and leak-free
3. Confirm master cylinder reservoir is filled to MAX line with fresh DOT 3 brake fluid
4. Ensure all bleeder screws are closed and dust caps are installed
5. Check that wheel lug nuts are torqued to specification

Verification

• With vehicle on level ground, pump brake pedal 10-15 times and verify firm pedal feel - pedal should be high and solid, not spongy
• Start engine and verify brake pedal does not sink when held under firm pressure for 60 seconds
• Perform low-speed brake test in safe area (empty parking lot): at 5-10 mph, apply brakes firmly and verify vehicle stops straight without pulling to either side
• Verify no brake fluid leaks at calipers, brake lines, or master cylinder after test stop
• Perform additional brake test at 15-20 mph in safe area, again verifying straight stops with firm pedal
• Check brake fluid level after test drives and top off if needed
• Listen for any unusual noises during braking (grinding, squealing beyond normal pad break-in)
• Allow 200-300 miles of normal driving for new seals to fully seat and brake performance to stabilize
• Do NOT perform hard stops or tow heavy loads for first 100 miles to allow proper break-in
• Re-check brake fluid level and inspect for leaks after first 50-100 miles of driving

Related trouble codes on this vehicle

Codes that commonly send this job to the bay — tap one for symptoms, causes, and diagnostic steps.

Chasing one of these codes and not sure which part is guilty? Ask a master mechanic about YOUR car →

More procedures for this vehicle