Solving 2007-2011 Lincoln Navigator Speed Sensor and Shifting Problems
Erratic shifting or a dead speedometer on your Navigator is likely more than just a simple sensor issue.
- The problem is usually the internal transmission lead frame, not a simple external sensor.
- Check with a dealer for recall (16V248) and extended coverage (TSB 19N01-S3) status for your VIN.
- This is not a beginner-friendly DIY repair; it requires dropping the transmission pan and valve body.
- Symptoms include erratic shifting, speedometer failure, and dangerous, sudden downshifts.
Is It a Sensor or the Lead Frame?
For the 2007-2011 Lincoln Navigator, the most common cause of speed sensor-related trouble isn't a simple, cheap, bolt-on sensor. The Output Shaft Speed (OSS) sensor is integrated into a part called the molded lead frame. This part is a complex electrical assembly that is mounted to the valve body, inside the transmission oil pan. Therefore, a failure often requires replacing the entire lead frame, not just a single sensor. This makes the repair more complex and costly than on other vehicles.
Known Issue: Recall and Extended Coverage
Ford issued a safety recall (NHTSA 16V248) for some 2011-2012 Navigators due to the OSS signal failing, which could cause a sudden, dangerous downshift into first gear. The fix was a software update for the PCM. Ford also released a Technical Service Bulletin (TSB 19N01-S3) that provided an extended warranty for the molded lead frame on some 2011 models. It is crucial to check with a Lincoln dealer to see if your vehicle had the recall performed or if it falls under any extended coverage.
Symptoms of a Failing Output Speed Sensor / Lead Frame
When the OSS sensor or the lead frame it's attached to begins to fail, the symptoms are hard to ignore. They often start intermittently and get worse over time.
- Harsh and Erratic Shifting: The transmission may slam into gear, delay shifts, or shift at the wrong times.
- Sudden Downshifting: The vehicle may unexpectedly downshift to a much lower gear, causing the engine to race and the vehicle to slow abruptly.
- Speedometer Failure: The speedometer may behave erratically, jumping around, or simply drop to 0 mph while driving.
- Check Engine or Wrench Light: The malfunction will trigger a warning light on your dashboard. Common trouble codes include P0720 and P0722. 🎬 Watch this detailed walkthrough for fixing P0720 and P0722 codes.
- Cruise Control Inoperative: The cruise control system will not engage because it cannot get a reliable speed reading.
Choosing the Right Aftermarket Part
Because the repair involves the entire lead frame, part quality is critical. This is not a repair you want to do twice.
- OEM (Motorcraft): The original Ford/Motorcraft part is the safest bet. Ford has updated the lead frame design over the years to improve reliability. Using a genuine part 🎬 See a quick tip on why these lead frames fail. ensures the best fit and function. The part number for the 6R80 lead frame is often AL3Z7G276D.
- Premium Aftermarket (e.g., Dorman): Brands like Dorman offer complete aftermarket lead frame assemblies. They are often a cost-effective alternative to OEM. Ensure you are buying the complete lead frame and not just a standalone sensor that won't fit your vehicle.
Pro Tip: When the lead frame is replaced, it is a perfect time to also replace the transmission fluid, filter, and the bulkhead connector sleeve (a common source of leaks) to prevent future problems.
Cost to Replace the Transmission Lead Frame
| Part / Service | Estimated Cost |
|---|---|
| New OEM Lead Frame | $250 - $400 |
| New Aftermarket Lead Frame | $150 - $300 |
| Shop Labor | $300 - $600 |
| Total Job Cost | $450 - $1000+ |
Note: Costs are estimates and will vary based on your location, the specific parts used, and shop labor rates. This does not include the cost of new transmission fluid or filter.
Frequently Asked Questions
Where is the Output Speed Sensor located on a 2007-2011 Navigator?
The sensor is not an external part. It is built into the molded lead frame, which is located inside the transmission oil pan and attached to the valve body.
Can I replace just the sensor?
No. For the 6R80 transmission in these Navigators, the entire molded lead frame assembly must be replaced to fix a faulty integrated Output Shaft Speed (OSS) sensor.
Is this a DIY job?
This is an advanced DIY job. It requires safely lifting the vehicle, draining the transmission fluid, removing the pan, and carefully removing the valve body to access the lead frame. Due to the complexity and risk of damaging other transmission components, this job is best left to experienced mechanics.
🎬 Watch: Step-by-step DIY tutorial for replacing the 6R80 lead frame.What are the error codes for a bad speed sensor?
The most common Diagnostic Trouble Codes (DTCs) are P0720 (Output Speed Sensor Circuit Malfunction) and P0722 (Output Speed Sensor No Signal). These codes point directly to an issue with the OSS sensor or its circuit within the lead frame.
Do I need to reprogram the computer after replacing the lead frame?
Generally, a new lead frame does not require reprogramming. However, it is always a good practice to clear all diagnostic trouble codes after the repair is complete and perform an adaptive learning drive cycle.
Helpful Videos
Technical Specifications
OEM Part Numbers: AL3Z7G276D
This part is the complete Molded Lead Frame for the 6R80 transmission, which includes the integrated Output Shaft Speed (OSS) sensor, Turbine Shaft Speed (TSS) sensor, Transmission Fluid Temperature (TFT) sensor, and Transmission Range (TR) sensor.
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- Lincoln Navigator: