This procedure covers the complete disassembly, cleaning, seal replacement, and reassembly of front brake calipers on 2016-2024 Hyundai Tucson models with the 2.5L I4 AWD engine.

Warnings

Tools required

Parts

• Front brake caliper rebuild kit (per side, includes seals, boots, and hardware) × 2 — Use OEM specification or equivalent
• Silicone brake grease (high temperature) × 1 — Permatex 24125 or equivalent
• Threadlocker (medium strength) × 1 — Loctite 243 or equivalent
• Brake cleaner spray × 2 — Non-chlorinated type
• Shop towels (lint-free) × 1 — Standard shop rags

Fluids

• DOT 4 Brake Fluid — 1 qt

Preparation

1. Park vehicle on level ground and place wheel chocks behind rear wheels
2. Remove approximately 2/3 of brake fluid from master cylinder reservoir using turkey baster or fluid transfer pump to prevent overflow during piston compression
3. Loosen front wheel lug nuts while vehicle is on ground
4. Raise front of vehicle and support securely on jack stands rated for vehicle weight
5. Remove both front wheels
6. Verify you have a complete rebuild kit for both calipers before beginning disassembly
7. Prepare clean workspace with all tools and parts organized
8. Put on appropriate protective equipment including chemical-resistant gloves and eye protection

Procedure

1. 1

   Remove caliper from vehicle
   Place a container under the caliper to catch brake fluid. Using a brake bleeder wrench, crack open the bleeder screw slightly to relieve pressure. Close bleeder screw. Remove the two caliper slide pin bolts using a 17mm socket. Carefully lift the caliper off the brake rotor and bracket. Mark or photograph the brake line orientation. Using a flare nut wrench, disconnect the brake line from the caliper body. Plug the brake line opening immediately with a clean rubber cap or plug to prevent fluid loss and contamination. Hang or secure the brake line away from the work area.
   Torque spec

   Caliper Slide Pin Bolts35 Nm (26 lb-ft)
2. 2

   Remove caliper piston using proper tool
   Place caliper on clean workspace with piston facing up. Remove the dust boot retaining ring or clip using a pick tool. Carefully peel away and remove the dust boot. Place several shop towels around the piston to catch any residual brake fluid. Using a caliper piston removal tool (threaded rod type or specialized pneumatic tool at very low pressure), carefully extract the piston from the caliper bore. Inspect the piston surface for scoring, wear, or corrosion. If any damage is present beyond light surface staining, the caliper must be replaced, not rebuilt.
   ⚠️NEVER use high-pressure compressed air directly to blow the piston out - it can eject violently causing serious injury. Use only proper piston removal tools or very low pressure (under 30 PSI) with extreme caution.
3. 3

   Remove piston seal from caliper bore
   Using a plastic or wooden pick tool (never metal tools that could scratch the bore), carefully extract the square-cut piston seal from the groove inside the caliper bore. Work carefully to avoid damaging the precision-machined bore surface. Inspect the bore thoroughly for any scoring, pitting, rust, or corrosion. Use a flashlight to examine the entire surface. Any significant damage requires caliper replacement. Measure the bore diameter with a caliper or micrometer if available and compare to specifications (typically 57mm for this application).
4. 4

   Clean all caliper components thoroughly
   Spray the caliper bore, piston, and all internal passages liberally with brake cleaner. Use a clean lint-free cloth to wipe all surfaces. Pay special attention to the seal grooves in the caliper bore and on the piston. Use a plastic or brass brush to clean the seal grooves gently if needed. Flush all brake fluid passages with brake cleaner. Spray and clean the exterior of the caliper body. Dry all components with compressed air at low pressure or allow to air dry completely. All parts must be absolutely clean and free of any contamination before reassembly.
5. 5

   Inspect and clean slide pins and hardware
   Remove the caliper slide pins from the bracket by pulling them from the rubber boots. Inspect the slide pins for wear, scoring, or corrosion. Clean the pins thoroughly with brake cleaner. Inspect the rubber boots for tears or deterioration and replace if damaged (usually included in rebuild kit). Clean the slide pin bores in the bracket. Remove any old grease and debris. The pins must slide smoothly without binding.
6. 6

   Install new piston seal
   Remove the new piston seal from the rebuild kit. Inspect it carefully for any damage or defects. Apply a thin coat of clean DOT 4 brake fluid to the seal. Carefully install the seal into the groove in the caliper bore, working it gently around the entire circumference. Ensure the seal is seated properly in the groove with no twists or folds. The seal should sit evenly in the groove all the way around.
7. 7

   Install piston into caliper bore
   Apply clean DOT 4 brake fluid liberally to the piston surface and the inside of the caliper bore. Ensure the piston is oriented correctly (flat side typically faces the pad). Carefully insert the piston into the bore, starting it straight to avoid cocking. Use hand pressure or a C-clamp with a flat block to slowly and evenly push the piston into the bore. The piston should slide in smoothly without excessive force. Push the piston all the way to the bottom of its travel.
8. 8

   Install new dust boot
   Remove the new dust boot from the rebuild kit and inspect for defects. Apply a small amount of silicone brake grease to the lip that contacts the piston. Stretch the boot over the piston, ensuring it seats in the groove on the piston body. Press the outer edge of the boot into the groove or over the retaining lip on the caliper body. Install the retaining ring or clip if equipped, ensuring it is fully seated. The boot should be properly sealed with no gaps or exposed areas.
9. 9

   Lubricate and install slide pins
   Apply a liberal coating of high-temperature silicone brake grease to the entire length of each slide pin. Do not use petroleum-based grease as it will damage rubber components. Install new slide pin boots onto the bracket if included in rebuild kit. Insert the slide pins into the bracket bores, ensuring they slide smoothly through the full range of travel. The pins should move freely without binding. Install new rubber boots, ensuring they are properly seated on both the pin and bracket.
10. 10

    Reinstall caliper to vehicle
    Remove the plug from the brake line. Clean the brake line fitting and caliper port threads with brake cleaner. Connect the brake line to the caliper and hand-thread to avoid cross-threading. Tighten the brake line fitting to snug, then an additional 1/6 turn using a flare nut wrench (do not overtighten). Position the caliper over the brake rotor and bracket. Apply a small amount of silicone brake grease to the slide pin bolt threads as specified. Install both caliper slide pin bolts and hand-tighten. Using a torque wrench, tighten the slide pin bolts to the specified torque in a cross pattern.
    Torque spec

    Caliper Slide Pin Bolts35 Nm (26 lb-ft)
11. 11

    Bleed brake system at rebuilt caliper
    Attach a clear plastic tube to the bleeder screw and place the other end in a container partially filled with clean DOT 4 brake fluid. Have an assistant pump the brake pedal 5-6 times and hold pressure. Open the bleeder screw approximately 1/2 turn using a brake bleeder wrench. Allow fluid and air to flow into the container until the pedal reaches the floor. Close the bleeder screw before the assistant releases the pedal. Repeat this process until no air bubbles appear in the discharged fluid and flow is steady. Check master cylinder fluid level frequently and add DOT 4 fluid as needed - never let it run dry. Tighten the bleeder screw to the specified torque when complete.
    ⚠Never allow the brake fluid reservoir to run empty during bleeding or air will enter the system requiring complete system bleeding.
    Torque spec

    Bleeder Screw10 Nm (7 lb-ft)
12. 12

    Repeat procedure for opposite side
    Perform steps 1 through 11 on the opposite front caliper. Work methodically and maintain the same attention to cleanliness and proper procedures. After both calipers are rebuilt and bled, verify the master cylinder is filled to the proper level with fresh DOT 4 brake fluid.
13. 13

    Final brake system verification
    With the vehicle still on jack stands, pump the brake pedal firmly 15-20 times. The pedal should become firm and not sink to the floor. If the pedal remains soft or spongy, additional bleeding is required. Check all brake line connections and caliper slide pin bolts for tightness. Inspect for any signs of brake fluid leakage around fittings, bleeder screws, or caliper seals. Wipe all components dry and wait 5 minutes, then recheck for any signs of seepage. Reinstall both front wheels and hand-tighten lug nuts. Lower vehicle to ground and torque lug nuts to specification in a star pattern.
    Torque spec

    Wheel Lug Nuts140 Nm (103 lb-ft)

Reassembly

1. Ensure all caliper slide pin bolts and brake line fittings are tightened to proper specifications
2. Verify bleeder screws are tight and dust caps are installed if equipped
3. Top off brake fluid reservoir to MAX line with fresh DOT 4 brake fluid
4. Dispose of used brake fluid and contaminated materials according to local environmental regulations
5. Clean any brake fluid spills from painted surfaces immediately to prevent damage

Verification

• Before moving vehicle, pump brake pedal until firm resistance is felt - pedal should not sink to floor with constant pressure
• Start engine and verify brake pedal height is normal and remains firm with engine running
• Perform initial brake tests at very low speed (under 5 mph) in a safe area to verify brakes engage properly on both sides
• Check for even braking with no pulling to either side
• Perform moderate brake applications from 15-20 mph several times to seat pads and verify proper operation
• Recheck brake fluid level after test drive and top off if needed
• After 50-100 miles of normal driving, recheck all caliper bolts for proper torque and inspect for any fluid leaks
• Monitor brake pedal feel and stopping performance for the first several hundred miles - any changes in pedal feel, pulling, or unusual noises require immediate inspection

More procedures for this vehicle