🔧 Optima - Rear Brake Pads & Rotor Replacement

You’ll remove the rear wheels, swap the rear pads and rotors, then reset the caliper piston so everything fits and works correctly. On some Optimа trims, the rear brakes use an electronic parking brake (EPB), which must be put in service mode before you retract the caliper.

Difficulty Level: Intermediate | Estimated Time: 2-4 hours

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⚠️ Safety & Precautions

• 🛑 Support the car with jack stands before working underneath.
• 🔥 Brakes get extremely hot; let them cool before starting.
• 🧯 Do not breathe brake dust; use brake cleaner, not compressed air.
• ⚡ If your Optima has Electronic Parking Brake (EPB), do not force the piston back without EPB service mode.
• 🔋 If using a scan tool for EPB service mode, keep the battery charged; low voltage can cause EPB faults.

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🔧 Required Tools

You'll need the following tools for this repair:

• Floor jack (rated 3-ton minimum)
• Jack stands (rated 3-ton minimum)
• Wheel chocks
• Safety glasses
• Nitrile gloves
• Torque wrench (20–150 ft-lbs range)
• 21mm socket
• 14mm socket
• 17mm socket
• Ratchet
• Breaker bar
• Flathead screwdriver
• Phillips screwdriver #2
• Caliper piston wind-back tool (specialty)
• Bungee cord
• Rubber mallet
• Wire brush
• Brake parts cleaner
• C-clamp (6 inch)
• Scan tool with EPB service mode (specialty)

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🔩 Required Parts

HowToo sells all the parts you need for this repair:

• Rear brake pad set - Qty: 1
• Rear brake rotors - Replace in pairs - Qty: 2
• Rear brake hardware kit (abutment clips) - Qty: 1
• Brake caliper grease (silicone) - Qty: 1
• Brake cleaner - Qty: 2 cans
• DOT 3 brake fluid - Qty: 1 quart
• Anti-seize compound - Qty: 1

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📋 Before You Begin

• Park on level ground, set the parking brake, and place wheel chocks at the front wheels.
• Loosen rear lug nuts 1/2 turn before lifting using a 21mm socket and breaker bar.
• EPB check: If your Optima has a parking brake button switch (not a foot pedal), you likely have EPB and should use a scan tool with EPB service mode before pushing/winding the piston back.
• Tip: Do one side at a time.

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🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Lift and secure the rear

• Use a floor jack to lift the rear of the car at the rear center jacking point.
• Set the car onto jack stands at the rear pinch welds or rear side support points.
• Remove the rear wheels using a 21mm socket.

Step 2: Put the parking brake system in the correct mode

• If you have EPB (button switch): Use a scan tool with EPB service mode (specialty) and command EPB Maintenance/Service Mode (sometimes called “Pad Replacement Mode”).
• If you have a manual parking brake (foot pedal): Release the parking brake fully and continue.
• Tip: EPB service mode prevents damage.

Step 3: Remove the caliper

• Turn the steering wheel straight and work on one rear corner.
• Remove the lower and upper caliper slide pin bolts using a 14mm socket and ratchet.
• Lift the caliper off the bracket. Hang it with a bungee cord so the brake hose is not stretched.
• Tip: Never let the caliper hang by the hose.

Step 4: Remove pads and caliper bracket

• Remove the old pads from the bracket by hand or with a flathead screwdriver.
• Remove the caliper bracket bolts using a 17mm socket and breaker bar.
• Torque to 98 Nm (72 ft-lbs) when reinstalling these bracket bolts.

Step 5: Remove the rotor

• If equipped with rotor retaining screws, remove them using a Phillips screwdriver #2.
• Tap the rotor hat with a rubber mallet to break it loose, then pull the rotor off.
• Clean the hub face with a wire brush and spray with brake parts cleaner.
• Apply a very thin film of anti-seize compound to the hub center (not the wheel studs).

Step 6: Install the new rotor

• Clean the new rotor with brake parts cleaner to remove packing oil.
• Install the rotor onto the hub. If it uses retaining screws, reinstall them snug using a Phillips screwdriver #2.

Step 7: Prep and install the bracket and pads

• Install new abutment clips from the rear brake hardware kit onto the bracket.
• Apply a light coat of brake caliper grease (silicone) where pad ears slide on the clips.
• Reinstall the caliper bracket using a 17mm socket and torque wrench. Torque to 98 Nm (72 ft-lbs).
• Install the new pads into the bracket by hand.

Step 8: Retract the caliper piston

• Remove the brake fluid reservoir cap under the hood (this helps fluid return).
• Use a caliper piston wind-back tool (specialty) to rotate and press the piston back slowly until it’s fully seated.
• Wind-back tool definition: A tool that turns the piston while pushing it in, needed on many rear calipers.
• If the piston will not retract and you have EPB, stop and re-check EPB service mode with the scan tool.

Step 9: Reinstall the caliper

• Slide the caliper over the new pads.
• Reinstall the slide pin bolts using a 14mm socket and torque wrench. Torque to 32 Nm (24 ft-lbs).

Step 10: Repeat on the other side

• Repeat Steps 3–9 on the other rear wheel.
• Tip: Replace pads/rotors in pairs.

Step 11: Reinstall wheels and torque lug nuts

• Reinstall wheels and hand-thread lug nuts.
• Lower the car off jack stands using the floor jack.
• Tighten lug nuts in a star pattern using a torque wrench. Torque to 107 Nm (79 ft-lbs).

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✅ After Repair

• Pump the brake pedal 10–15 times until it feels firm before driving.
• Check brake fluid level and top off with DOT 3 brake fluid if needed.
• If you used EPB service mode, use the scan tool to exit service mode, then apply/release EPB a few times to confirm normal operation.
• Do a careful test drive: start slow, verify no grinding, pulling, or warning lights.
• Pad bedding: Make 6–10 smooth stops from 35–5 mph with cool-down time between stops.

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💰 DIY vs Shop Cost

Shop Cost: $450-$850 (parts + labor)

DIY Cost: $160-$380 (parts only)

You Save: $290-$470 by doing it yourself!

Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 2-3 hours.

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🎯 Ready to get started?

HowToo makes it easy: same-day/2-day shipping on every part, plus all the tools and specialty tools you need! Check out the parts and tools sections below to add everything to your cart.