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2012 GMC Sierra 1500
1999 - 2013 GMC Sierra 1500
SL
Compatible with more variants.
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2014-2018 Chevy Silverado & GMC Sierra Rear Taillight Signal Bulb Replacement

2014-2018 Chevy Silverado & GMC Sierra Rear Taillight Signal Bulb Replacement

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Tools & Fluids

7mm
7mm
Socket
or (1/4")
1/2
1/2
Ratchet
Flathead
Flathead
Screwdriver
Trim
Trim
Tool
Leather
Leather
Gloves
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How to Replace Rear Turn Signal Bulbs on a 2012 GMC Sierra 1500

Step-by-step instructions with tools, parts, safety tips, and testing guidance for 1999, 2000, 2001, 2002, 2003, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013

How to Replace Rear Turn Signal Bulbs on a 2012 GMC Sierra 1500

Step-by-step instructions with tools, parts, safety tips, and testing guidance for 1999, 2000, 2001, 2002, 2003, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013

Orion
Orion

🔧 Rear Turn Signal Bulb Replacement

The rear turn signal bulb is replaced by removing the taillamp assembly, swapping the bulb in the socket, and reinstalling everything. On your Sierra, this is a simple job if the lamp housing releases cleanly and the socket is not heat-damaged.

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


⚠️ Safety & Precautions

  • Park on level ground and set the parking brake.
  • Turn the headlight switch off before starting.
  • Let the bulbs cool before touching them.
  • Do not touch the glass of a halogen bulb with bare hands.
  • If a socket is melted or loose, replace it before driving.

🔧 Required Tools

You'll need the following tools for this repair:

  • 7mm socket
  • Ratchet
  • Small flat-blade screwdriver
  • Trim panel tool
  • Gloves
  • Safety glasses

🔩 Required Parts

HowToo sells all the parts you need for this repair:

  • Rear turn signal bulb - Qty: 2

📋 Before You Begin

  • Park with the steering wheel straight and the transmission in Park.
  • Open the tailgate for easier access if needed.
  • Replace bulbs in pairs so both rear turn signals match brightness and color.

🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Open access to the taillamp

  • Open the tailgate.
  • Use a 7mm socket and ratchet to remove the two taillamp fasteners.
  • Pull the taillamp housing straight rearward to release the alignment pins.
  • Pull evenly to avoid cracking the lens.

Step 2: Remove the bulb socket

  • Locate the turn signal bulb socket on the back of the taillamp.
  • Twist the socket counterclockwise by hand and remove it.
  • If it is tight, use a small flat-blade screwdriver carefully on the tab.

Step 3: Replace the bulb

  • Remove the old bulb from the socket by pulling it straight out.
  • Install the new bulb into the socket firmly.
  • Make sure the bulb is fully seated and straight.
  • Match the bulb base shape before forcing it.

Step 4: Reinstall the socket and taillamp

  • Insert the socket back into the taillamp housing.
  • Twist clockwise until it locks.
  • Reinstall the taillamp housing into the body.
  • Use the 7mm socket and ratchet to tighten the fasteners.
  • Torque to snug fit only; do not overtighten the plastic housing.

Step 5: Test the repair

  • Turn the ignition on.
  • Activate the left and right turn signals.
  • Check that the repaired side flashes normally.
  • Confirm the brake light and tail light still work.

✅ After Repair

  • Verify both rear signals flash at the same brightness.
  • Check for a loose taillamp housing after a short drive.
  • If the new bulb does not light, recheck the socket and the fuse.

💰 DIY vs Shop Cost

Shop Cost: $60-$140 (parts + labor)

DIY Cost: $10-$30 (parts only)

You Save: $50-$110 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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