Safety Warning

DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.

2021 Lincoln Navigator Base, 4WDFACTORY OEM SERVICE PROCEDURE

Gear Shift Module (GSM): Installation

To install, reverse the removal procedure.
1. Seat both sides of the ambient light bar around the GSM.
2. Seat the passenger side of the ambient light bar.
3. Seat the center right of the ambient light bar.
4. Seat the center left of the ambient light bar.
5. Verify the P and D buttons move up and down freely.

Courtesy of FORD MOTOR COMPANY

Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.
• Brakes feel soft, pull hard to one side, or make grinding noises.
• The engine overheats, stalls repeatedly, or misfires under load.
• You are missing required tools, torque specs, or safe lifting equipment.
• You are not confident in the next step or safety outcome.