Lincoln Navigator sudden acceleration problems

Filed Jul 13, 2026 · Transmission · 77,000 miles · VA

The contact owns a 2019 Lincoln Navigator. The contact stated that while driving at 40 MPH, the transmission unexpectedly downshifted. Additionally, while slowing down and driving under 40 MPH, the transmission experienced a rough downshift, causing the passengers inside the vehicle to lunge forward from their seats. The vehicle was taken to an independent mechanic, who flushed the transmission, but the failure persisted. The contact later received notification of the federal safety agency Campaign Number: 26V402000 (Power Train); however, the part to do the recall repair was not yet available. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The dealer was made aware of the failure but confirmed that parts were not yet available. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 77,000.

Filed Feb 10, 2026 · Acceleration, Engine · TX

While driving, the vehicle repeatedly hesitated during gear changes, lost power, and then abruptly jerked back into gear. This occurred intermittently for over a month without any warning messages, creating unpredictable and unsafe driving conditions. As the issue worsened, the vehicle began losing power more frequently. The most serious event occurred at highway speed, where the vehicle suddenly lost propulsion in the middle of active traffic, nearly causing a stall. This created an immediate safety hazard for myself and surrounding drivers. After several seconds, the vehicle violently re-engaged into gear and surged forward. Only at this point did the vehicle display a warning: “Powertrain Malfunction / Reduced Power.” I scanned the vehicle and retrieved DTC P0734 – Gear 4 Incorrect Ratio, a code associated with internal transmission faults. A dealership inspected the vehicle and reported that the CDF drum had failed. They stated they could not guarantee that replacing the drum would resolve all issues and provided two estimates: $5,600 for a partial internal repair/$8,700 for full transmission replacement. The 10R80 transmission has a documented history of failures, including harsh shifting, slipping, unexpected gear disengagement, and internal component defects. These issues are addressed in multiple Ford Technical Service Bulletins involving P0734, harsh/failed shifts, and failures related to the CDF clutch cylinder/drum. Many vehicles of the same make and model are covered under related recalls or service actions for similar problems; however, my VIN is not included, and Lincoln declined to honor the existing recall. This defect presents a serious safety risk due to: Sudden loss of power while driving, including at highway speeds, Unpredictable re-engagement and violent surging, Loss of propulsion without warning, leading to near-stall conditions. This powertrain malfunction is a known, unsafe, repeat issue among these vehicles equipped w/this transmission.

Filed Feb 10, 2025 · Engine, Transmission · 86,000 miles · IN

The contact owns a 2018 Lincoln Navigator. The contact stated that while driving at an undisclosed speed, the vehicle lost motive power. The vehicle lunged forward. Additionally, the contact stated that the vehicle was shifting roughly. The contact stated that the vehicle would redline. There were no warning lights illuminated. The vehicle was taken to the local dealer, where it was determined that a transmission flush was needed. The vehicle was repaired, but the failure recurred. The vehicle was taken back to the same local dealer, who was unable to determine the cause of the failure. The manufacturer was contacted, but no additional assistance was provided. The failure mileage was approximately 86,000.

Filed Mar 15, 2017 · Acceleration, Engine · 110,000 miles · ID

Tl* the contact owns a 2007 lincoln navigator. While starting the vehicle and depressing the brake pedal, the vehicle suddenly accelerated and the rpms increased. The contact had to shift the vehicle into neutral for the rpms to decrease. The contact mentioned that this was the second time the failure occurred. The vehicle was not diagnosed or repaired. The manufacturer was notified of the issue. The failure mileage was 110,000.

Filed Mar 5, 2015 · Lights · MN · crash

Started with the light in vehicle staying on for hours at a time causing a loud noise under hood. While driving and picking up my girlfriend, we were scared by the sudden acceleration of my vehicle. We hit another car causing our heads to hit the dash board. The car wouldn't stop so after we hit a car while on breaks, I through car in park and that just made car engine roar even louder causing engine to go into danger mood. Turned car off and started back up it was still roaring but then calm down to normal.

Filed Jun 23, 2014 · Acceleration · 140,000 miles · WI

Tl * the contact owns a 2007 lincoln navigator. While driving 50 MPH, the vehicle suddenly accelerated independently. The vehicle was not diagnosed or repaired. The manufacturer was not notified. The VIN was unavailable. The failure mileage was 140,000.

Filed Dec 29, 2010 · Acceleration · 300 miles · NY

Tl*the contact rented a 2011 lincoln navigator. The contact stated that while driving approximately 50 MPH, the vehicle suddenly accelerated to 70 MPH and when the contact attempted to slow down, it did not respond. The vehicle was able to stop by placing it in low gear and removing the key from the ignition. The vehicle was towed to a dealer but they were unable to give him any details as it was a rental vehicle. The repairs were unknown. The failure mileage was approximately 300. Updated 2/17/11 *cn updated 04/27/11

Filed Dec 23, 2009 · Acceleration · 56,717 miles · NJ

Tl*the contact owns a 2005 lincoln navigator. He stated that the cruise control was engaged at 45 MPH and the vehicle suddenly accelerated to 65 MPH when the brake was tapped to slow the vehicle down repeated attempts were made to slow the vehicle down. The dealer confirmed that the accelerator mat entrapment caused the failure. He also stated that his vehicle is equipped with a pedal adjustment for taller drivers. The dealer replaced the floor mat hooks and made sure that it was not close to the accelerator pedal. The failure and the current mileage was 56,717. Updated 01/15/10. *lj the dealer found the all season mat stuck under the gas and brake. They removed the carpet mat and installed an all weather mat hook. Updated 01/19/10.

Filed Mar 2, 2005 · Acceleration · 6 miles · TX

Vehicle experienced a problem with the idle speed. When pulling out of a parking space vehicle lunged forward. Meantime, the vehicle was idling at 2500 rpms. Owner contacted the dealer and the manufacturer, and no one seemed to know how to resolve this problem. *ak the consumer stated that the engine takes 2-5 minutes for idle speed to come down from 2500 rmp.

Filed May 14, 2004 · Acceleration · 6,000 miles · NY

While reversing pedal stuck to the floor, and vehicle experienced sudden acceleration.