🔧 Optima - Rear Brake Pad Replacement

You’ll remove the rear wheels, swing the rear brake calipers out of the way, replace the pads (and hardware if included), then reset everything and verify the brakes feel normal. On your Optima, the rear caliper piston often must be pushed in (and sometimes rotated) to make room for the thicker new pads.

Difficulty Level: Intermediate | Estimated Time: 1.5-3.0 hours

Assumption: Rear caliper piston requires a wind-back tool; EPB steps included if equipped.

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⚠️ Safety & Precautions

• ⚠️ Work on a flat, solid surface; use jack stands—never rely on a jack alone.
• ⚠️ Keep the key fob away from the car (10+ feet) and keep ignition OFF while working.
• ⚠️ Do not press the brake pedal with a caliper removed.
• ⚠️ Brake dust is harmful—use brake cleaner, not compressed air.
• ⚠️ Hybrid note: avoid touching any orange high-voltage wiring (not normally near brakes).
• ⚠️ If equipped with an Electronic Parking Brake (EPB), put it in service mode before pushing pistons in.

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🔧 Required Tools

You'll need the following tools for this repair:

• Floor jack (rated 2-ton minimum)
• Jack stands (rated 2-ton minimum)
• Wheel chocks
• 21mm socket
• 1/2" drive breaker bar
• 1/2" drive torque wrench (20-150 ft-lbs range)
• 3/8" drive ratchet
• 3/8" drive torque wrench (10-80 ft-lbs range)
• 14mm socket
• 17mm socket
• Open-end wrench set (14mm)
• Flat trim tool
• Needle-nose pliers
• Disc brake piston wind-back tool (specialty)
• Brake caliper hanger hook (specialty)
• Wire brush
• Catch pan
• Nitrile gloves
• Safety glasses
• 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 pad hardware/clip kit - Qty: 1
• Brake caliper slide pin grease (silicone-based) - Qty: 1
• Brake parts cleaner - Qty: 1
• Rear brake rotors - Qty: 2 (optional if worn, grooved, or below spec)

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📋 Before You Begin

• 🧰 Park on level ground, set the parking brake (unless EPB service mode is needed), and chock the front wheels.
• 🧰 Open the hood and locate the brake fluid reservoir; you’ll watch the level as pistons are pushed back.
• 🧰 If your Optima has EPB: retract it with Scan Tool > EPB > Pad Replacement Mode before compressing pistons.
• 🧰 Break the rear lug nuts loose 1/4 turn using a 21mm socket and breaker bar before lifting.

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🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Lift and support the rear

• Place wheel chocks at the front wheels.
• Lift the rear using a floor jack at the approved rear jacking point.
• Set the car securely on jack stands under the rear pinch welds or rear support points.

Step 2: Remove the rear wheels

• Remove lug nuts with a 21mm socket and 1/2" drive breaker bar.
• Remove both rear wheels and set them under the car as an extra safety back-up.

Step 3: Confirm parking brake type (EPB vs cable)

• Look at the rear caliper area: if you see an electric motor on the caliper, it’s EPB.
• If you see a cable lever attached to the caliper, it’s a cable parking brake.
• Wind-back tool rotates and presses piston in.

Step 4: Put EPB into service mode (if equipped)

• Connect your scan tool with EPB service mode (specialty).
• Command: EPB > Pad Replacement Mode / Retract.
• Verify the EPB motors retract fully before continuing.

Step 5: Remove the rear caliper bolts

• Turn the steering wheel is not needed for the rear; just position yourself for access.
• Hold the slide pin with a 14mm open-end wrench if it spins.
• Remove the caliper slide bolts using a 14mm socket and 3/8" drive ratchet.
• Torque to 25 Nm (18 ft-lbs) on reassembly.

Step 6: Support the caliper safely

• Lift the caliper off the bracket and hang it using a brake caliper hanger hook (specialty).
• Do not let the caliper hang by the brake hose.

Step 7: Remove old pads and hardware

• Pull the inner and outer pads out of the bracket by hand; use a flat trim tool if stuck.
• Remove pad abutment clips (hardware) with a flat trim tool.
• Clean the bracket pad “shelves” with a wire brush and spray with brake parts cleaner into a catch pan.

Step 8: Retract the rear caliper piston

• Check the brake fluid reservoir level before compressing; fluid may rise.
• Use the disc brake piston wind-back tool (specialty) to slowly press the piston in.
• If the piston will not push straight in, rotate while pressing with the same tool (common on rear calipers).
• Stop when the piston face is fully seated and level.

Step 9: Service the slide pins

• Pull the slide pins out of the bracket by hand (note which pin goes where).
• Wipe old grease off, then apply a thin coat of brake caliper slide pin grease (part from your list).
• Reinsert pins and confirm they move smoothly.

Step 10: Install new hardware and pads

• Install new abutment clips onto the bracket by hand; press them fully seated.
• Install the new pads into the bracket.
• Make sure the pad “ears” slide freely in the clips; if tight, re-clean with wire brush and brake parts cleaner.

Step 11: Reinstall the caliper

• Lower the caliper over the new pads.
• Install the slide bolts by hand first to avoid cross-threading.
• Tighten with a 14mm socket and 3/8" drive torque wrench.
• Torque to 25 Nm (18 ft-lbs).

Step 12: Reinstall wheels and torque lug nuts

• Install wheels and hand-thread lug nuts.
• Snug lug nuts in a star pattern using a 21mm socket.
• Lower the car off the jack stands using the floor jack.
• Final-tighten lug nuts with a 1/2" drive torque wrench: Torque to 90-110 Nm (66-81 ft-lbs).

Step 13: Restore brake pressure

• Before starting the car, pump the brake pedal 10-15 times until it feels firm.
• Check brake fluid level and top off only if needed.

Step 14: Re-engage EPB (if equipped)

• Use the scan tool with EPB service mode (specialty) to run: EPB > Exit Service Mode / Apply.
• Cycle the EPB switch to confirm normal operation.

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✅ After Repair

• ✅ With the car still parked, press the brake pedal firmly and hold 10 seconds; confirm it does not sink.
• ✅ Test drive at low speed first; confirm no pulling, grinding, or warning lights.
• ✅ Perform a gentle bed-in: 6-8 moderate stops from 30→5 mph, with cool-down between stops.
• ✅ Recheck lug nut torque after 25-50 miles using a 1/2" drive torque wrench.

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💰 DIY vs Shop Cost

Shop Cost: $250-$450 (parts + labor)

DIY Cost: $60-$160 (parts only)

You Save: $190-$290 by doing it yourself!

Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 1.5-2.5 hours.

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🎯 Ready to get started?

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