🔧 Rear Window Regulators - Replacement

Assumption: both rear door window regulators are being replaced, left and right. On your Sierra, the rear door trim panel comes off first, then the glass and regulator assembly are removed from each rear door. GM typically uses rivets on these doors, so the old regulator usually has to be drilled out and the new one installed with hardware or supplied fasteners.

Difficulty Level: Intermediate | Estimated Time: 3-5 hours

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⚠️ Safety & Precautions

• Disconnect the negative battery cable before starting. Rear doors contain side airbag components and wiring.
• Keep the ignition off and wait at least 2 minutes after disconnecting the battery before unplugging door connectors.
• Support the window glass any time the regulator is disconnected. Tape it in place so it does not drop.
• Wear safety glasses when drilling out rivets. Metal chips will fall inside the door.
• Work carefully around the window glass edge. It can break or cut skin easily.

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🔧 Required Tools

You'll need the following tools for this repair:

• 10mm socket
• 7mm socket
• 1/4-inch socket
• Ratchet
• Short extension
• Trim panel removal tool
• Small flat-blade screwdriver
• Torx T20 screwdriver
• Torx T30 screwdriver
• 1/4-inch drill bit
• Drill
• Rivet gun (specialty)
• Window glass suction cup
• Masking tape
• Torque wrench
• Gloves
• Safety glasses

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🔩 Required Parts

HowToo sells all the parts you need for this repair:

• Left rear window regulator assembly - Qty: 1
• Right rear window regulator assembly - Qty: 1
• Door panel retainers - Qty: 1 set
• Plastic vapor barrier adhesive tape - Qty: 1 roll
• Regulator mounting rivets or fasteners - Qty: 1 set

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📋 Before You Begin

• Park on level ground and set the parking brake.
• Lower each rear window slightly if it still moves. If not, you can work with the glass taped in place.
• Disconnect the negative battery cable before removing either rear door panel.
• Keep screws organized by door.

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🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Disconnect power

• Use a 10mm socket to remove the negative battery cable.
• Wait at least 2 minutes before touching door connectors.

Step 2: Remove the rear door panel

• Use a 7mm socket and Torx T20 screwdriver to remove the visible door panel screws.
• Use a trim panel removal tool to release the lower and side clips.
• Lift the door panel upward to unhook it from the window ledge.
• Disconnect the electrical connectors and set the panel aside.

Step 3: Remove the moisture barrier

• Use a small flat-blade screwdriver to carefully lift the adhesive edges.
• Peel the vapor barrier back slowly and keep it clean so it can be reused.

Step 4: Secure the window glass

• If the glass is still in the door, raise it by hand if possible.
• Use masking tape to hold the glass to the door frame.
• Do not let the glass hang loose.

Step 5: Unbolt or drill out the old regulator

• Use a 1/4-inch drill bit and drill to remove the factory rivets if your door uses rivets.
• If your replacement uses bolts, remove the regulator fasteners with a 10mm socket.
• Support the regulator as you remove the last fastener so it does not drop inside the door.

Step 6: Disconnect the regulator and remove it

• Use a Torx T30 screwdriver or 10mm socket to remove the glass clamps from the regulator.
• Lower or slide the glass carefully out of the regulator tracks.
• Remove the old regulator assembly through the door opening.

Step 7: Install the new regulator

• Feed the new regulator into the door opening and position it in place.
• Install the mounting fasteners by hand first.
• Torque regulator bolts to 9 N·m (80 in-lbs) if bolts are used.
• If rivets are used, install the supplied rivets with a rivet gun (specialty).

Step 8: Reattach the glass

• Lower the taped glass into the regulator clamps.
• Use a 10mm socket or Torx T30 screwdriver to tighten the glass clamp fasteners.
• Torque glass clamp fasteners to 9 N·m (80 in-lbs).
• Remove the tape and cycle the glass by hand a small amount to confirm it moves freely.

Step 9: Test the window before reassembly

• Temporarily reconnect the battery and test the window switch.
• Make sure the glass travels evenly and does not bind.
• Disconnect the battery again before reinstalling the door panel if you need to adjust anything.

Step 10: Reinstall the moisture barrier and door panel

• Press the vapor barrier back into place with its original adhesive.
• Reconnect the electrical connectors and align the door panel clips.
• Use your hands and then a trim panel removal tool to snap the panel into place.
• Install the screws with a 7mm socket and Torx T20 screwdriver.

Step 11: Repeat on the other rear door

• Use the same process for the opposite rear door.
• Work one side at a time.

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✅ After Repair

• Reconnect the negative battery cable with a 10mm socket.
• Cycle each rear window fully up and down several times.
• Listen for grinding, skipping, or uneven movement.
• Check that both door panels sit flush and all switches work.
• If a window has auto-up/down, perform the relearn if needed by holding the switch fully up for a few seconds after full closure.

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💰 DIY vs Shop Cost

Shop Cost: $500-$1,000 (parts + labor)

DIY Cost: $180-$400 (parts only)

You Save: $320-$600 by doing it yourself!

Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 2.5-4 hours.

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🎯 Ready to get started?

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