🔧 Taillight Bulb Replacement - Bulb Swap

This procedure covers replacing both rear taillight bulbs on your Sierra, assuming it has bulb-type taillamps. If your truck has factory LED taillamps, the bulb cannot be replaced separately and the full lamp assembly must be replaced instead.

Difficulty Level: Beginner | Estimated Time: 0.5-1 hour

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⚠️ Safety & Precautions

• Turn the lights off before starting.
• Let the bulbs cool completely if they were recently on; bulbs get very hot.
• Do not touch the glass on a new bulb with bare fingers. Oil from your skin can shorten bulb life.
• If you are working near the rear bumper, keep the truck in Park with the parking brake set.
• No battery disconnect is required for this repair.

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🔧 Required Tools

You'll need the following tools for this repair:

• 7mm socket
• Ratchet
• Trim panel tool
• Gloves
• Safety glasses

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🔩 Required Parts

HowToo sells all the parts you need for this repair:

• Rear taillight bulbs - Qty: 2

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📋 Before You Begin

• Park on level ground.
• Shift into Park and set the parking brake.
• Turn the headlight switch off.
• Open the tailgate for better access.

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🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Open the tailgate and access the taillamp screws

• Lower the tailgate.
• Use a 7mm socket and ratchet to remove the two taillamp retaining screws on the side you are servicing.

Step 2: Remove the taillamp assembly

• Pull the taillamp straight rearward to release the locating pins.
• If it feels stuck, use a trim panel tool carefully at the edge.
• Pull straight back, not sideways.

Step 3: Remove the bulb socket

• Twist the bulb socket counterclockwise by hand and remove it from the housing.
• Remove the old bulb from the socket.

Step 4: Install the new bulb

• Install the new bulb into the socket.
• Make sure it is fully seated and locked in place.
• Reinstall the socket into the taillamp housing and twist clockwise to lock.

Step 5: Reinstall the taillamp assembly

• Align the taillamp locating pins with the body openings.
• Push the lamp straight in until it seats fully.
• Reinstall the two screws with the 7mm socket and ratchet.
• Torque to 3.5 Nm (31 in-lbs).

Step 6: Repeat on the other side

• Repeat the same steps for the opposite taillight bulb.

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✅ After Repair

• Turn on the parking lights and check both taillights.
• Press the brake pedal and verify both brake lights work.
• Test the turn signals and reverse lights if applicable.
• If a bulb does not light, recheck socket seating and bulb orientation.

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💰 DIY vs Shop Cost

Shop Cost: $120-$220 (parts + labor)

DIY Cost: $20-$50 (parts only)

You Save: $100-$170 by doing it yourself!

Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 0.5-1 hour.

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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.