2021 Ford F-150: shudder or vibration when accelerating

Filed Oct 20, 2026 · Transmission · 78,000 miles · TX

The contact owns a 2021 Ford F-150. The contact stated that the vehicle was scheduled for repair under the federal safety agency Campaign Number: 26V402000 (Power Train); however, the part to complete the recall repair was not yet available. The contact stated that while driving at an undisclosed speed, the vehicle suddenly shuddered, and manual mode was utilized to bypass 5th gear and upshift into 6th gear. A warning message reading "Service Recall" was displayed. The local dealer was notified on several occasions. Another local dealer, where the vehicle was originally purchased, was contacted for a second opinion. The manufacturer was notified of the failure via telephone. The failure mileage was approximately 78,000.

Filed Oct 3, 2026 · Transmission · IA

Vehicle: 2021 Ford F-150 Tremor Mileage: Approximately 103,000 miles My 2021 Ford F-150 Tremor developed a severe shudder and vibration during acceleration. The condition progressively worsened and became significant enough that I had the vehicle professionally inspected. The vehicle was diagnosed with a failing torque converter as the cause of the acceleration shudder/vibration. The truck has been well maintained throughout my ownership. It is garage kept and receives regular maintenance through an authorized Ford service facility. I have maintenance records documenting the vehicle’s service history. My concern is that the torque-converter failure produces a severe vibration/shudder during acceleration and has progressively worsened. I am concerned about the potential safety implications if the torque converter or transmission continues to deteriorate while the vehicle is being driven. I contacted Ford regarding the failure and requested assistance with the repair. The vehicle is outside Ford’s original powertrain warranty at approximately 103,000 miles, and Ford declined to provide assistance. I am submitting this complaint so the federal safety agency has a record of this torque-converter/transmission failure and the severe acceleration shudder occurring in my 2021 Ford F-150.

Filed Sep 11, 2026 · Engine, Transmission · MO

I am reporting a severe safety defect where Ford Motor Company's sequential safety recall software updates are actively corrupting powertrain modules and inducing physical mechanical failures while the vehicle is in operation.Following the completion of the 24S55 Engine Intake Valve Recall (which reflashed the PCM and wiped the transmission's adaptive learning tables), my 2021 Ford F-150 developed an immediate operational shudder. Shortly after, a forced Over-the-Air (OTA) update for the 26C10 Trailer Brake Module triggered a secondary network reset via the CAN-bus. The intersection of these two software-driven actions caused an operational fault that physically broke the torque converter clutch.A compromised torque converter clutch can cause sudden vehicle stalling, unpredictable acceleration lags, and catastrophic powertrain locking while driving at highway speeds, creating an imminent crash hazard. The local Ford dealership service department confirmed the hardware failure and noted that pushing automated software updates over unstable tables leaves the entire transmission highly vulnerable to total systemic failure.Ford is currently refusing to open an escalation file or address this issue. Because Ford's official remedy for safety recalls 24S55 and 26C10 directly introduces a secondary, severe safety risk to the vehicle's powertrain integrity, I request that the federal safety agency investigate the technical compatibility and safety of these sequential software updates.

Filed Apr 4, 2026 · Transmission · TX

Transmission is shuddering at speeds up to 60mph. Can cause the vehicle to jump repeatedly.I am worried at such a high speed the vehicle could lose control and put my life and others at risk. Also can shift very hard when coming to a stop so much so that it feels like I’ve been hit from behind by another vehicle. I’ve never had any type of messages or warning lights prior or post. After searching up issue I have found hundreds and hundreds of other vehicle owners with the 10r80 transmission to be experiencing similar problems. Ford has acknowledged the problem and have a fix but at a high cost. Some people are not able to repair vehicles at that moment could be putting themselves and other at risk of death or injury.

Filed Mar 19, 2026 · Transmission · MA

I put the truck into reverse and tried to back out of my driveway. The truck didn't move for several seconds, then started to move. I brakes, shifted into drive and the truck continued to move backwards. I applied the brakes and the transmission seemed to spin before it moved forward. I drove down the street to the corner. I applied the brakes and the was a shudder and bang as the transmission downshifted from 4th to 3rd. This occurs intermittently over the last 3 months. When I searched online, I learned that these symptoms are consistent with those described in Ford TSB 23-2350. I had an independent mechanic confirm the problem and he noted the fluid was dark. Whrn I spoke to the dealership, they tried to explain the issue was due to the transmission being cold. I'm the original owner of the truck.

Filed Feb 18, 2026 · Fuel system, Transmission · 60,000 miles · FL

The contact owns a 2021 Ford F-150. The contact stated that while stopped, the vehicle hesitated and shuddered while depressing the accelerator pedal. There was no warning light illuminated. The vehicle stopped in the middle of the road and failed to move even while in neutral(N). Due to the failure, the vehicle was towed to the dealer, where it was diagnosed with a defective fuel pump. The contact was informed that the VIN was included in the federal safety agency Campaign Number: 25V455000 (Fuel System, Gasoline); however, the parts for the recall repair were not yet available. The contact was provided with an estimate for the repair, which the contact approved. The vehicle was repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 60,000.

Filed Dec 23, 2025 · Acceleration, Engine · CO

Description of Incident: The vehicle exhibits a severe and unpredictable transmission "shudder," "stutter," and hesitation during gear synchronization, specifically during 1st–3rd and 8th–10th gear transitions. This manifest as a violent "shaking" sensation and a loss of momentary acceleration while merging into high-speed traffic. This issue was first reported to an authorized Ford dealership on December 17, 2024. At that time, the vehicle exhibited harsh shifting and "shuddering" consistent with Ford Technical Service Bulletin (TSB) 22-2428. Despite being under a 150,000-mile service contract, the dealer misdiagnosed the mechanical transmission defect as an engine misfire, resulting in ineffective repairs. The defect has persisted and worsened. The internal failure has been identified as a defective CDF Clutch Drum (Cylinder) where an internal bushing moves out of place, obstructing fluid flow and causing mechanical "slip." This is a known manufacturing defect documented in multiple Ford TSBs (22-2428, 23-2250, and 24-2101). Safety Risk: The failure causes unpredictable power delivery. On multiple occasions, the vehicle has hesitated or "stuttered" while attempting to merge onto highways or cross intersections, leaving the vehicle vulnerable to side-impact or rear-end collisions. The lack of consistent throttle response and the violent nature of the shifting creates a significant safety hazard for the driver and surrounding motorists. Verification/Inspection: The symptoms were reported to a Ford dealership multiple times. As of December 2025, the dealership has opened a formal case with the manufacturer to verify the internal "cause of failure" by the Shop Foreman. No warning lamps or Diagnostic Trouble Codes (DTCs) appeared on the dashboard, as the failure is a mechanical internal bushing slip that does not always trigger a software sensor until total failure occurs. The vehicle is available for inspection.

Filed Aug 6, 2025 · Fuel system · 88,000 miles · IN

The contact owns a 2021 Ford F-150. The contact stated that while driving at an undisclosed speed, the accelerator pedal was depressed; however, the vehicle failed to accelerate as intended. No warning light was illuminated. In addition, the transmission shuddered. The vehicle was not diagnosed or repaired by an independent mechanic or dealer. The dealer was made aware of the failure; however, the contact was informed that the parts were not available. The contact received notification of the federal safety agency Campaign Number: 25V455000 (Fuel System, Gasoline); however, parts were not yet available. The manufacturer was made aware of the failure, and a case was filed. The contact was advised to contact the federal safety agency Hotline to report the failure. The failure mileage was approximately 88,000.

Filed Jul 18, 2024 · Electrical, Engine · 4,000 miles · PA

The contact owns a 2021 Ford F-150. The contact stated that the vehicle was shuddering and jerking while driving. The check engine warning light was flashing. The contact stated there was another unknown warning light flashing. The contact stated that the soy-based wiring was causing costly repairs. The vehicle was taken to the local dealer, where it was diagnosed that the wiring in the undercarriage was chewed on. The vehicle was repaired, but the failure recurred a month later. The contact stated that while driving 35–40 MPH, an unknown warning light started to flash. The vehicle was taken back to the local dealer, where it was diagnosed and determined that the soy-based wiring had been chewed on by squirrels and chipmunks. The vehicle was repaired. The manufacturer was contacted and referred to the federal safety agency Hotline. The failure mileage was approximately 4,000.

Filed May 1, 2023 · Brakes · 45,000 miles · NH

The contact owns a 2021 Ford F-150. The contact stated that while driving at an undisclosed speed, the vehicle shuddered. The contact related the failure to the federal safety agency Campaign Number: 21V533000 (Service Brakes, Hydraulic). The vehicle was taken to the dealer where it was repaired, however, the VIN was not included in the recall. The manufacturer was made aware of the failure. The failure mileage was approximately 45,000.

Filed Jul 14, 2022 · Transmission · ME

truck lurches and shudders when sifting, been back to dealer several times but they can't fix the problem.

Filed Mar 14, 2022 · Engine · 4,000 miles · MD · fire

The contact owns a 2021 Ford F-150. The contact stated that while driving the vehicle suddenly began to shudder and vibrate. Later, the vehicle would not start and message "system failure" had displayed. A clicking noise and burning odor was present coming from the engine compartment had occurred and the contact exited the vehicle. The cause of the failure was not determined. The local dealer was notified of the failure. The manufacturer was not yet notified. The failure mileage was 4,000. 3/12 While spuddering would not start and dash panel system failure. clicking sound and burning odor coming from the motor.