There are 2 owner-reported powertrain & transmission complaints for the 2026 Toyota 4Runnerin NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
At approximately 520 miles, while performing a low speed left hand turn, the vehicle experienced a sudden mechanical "thunk" in the drivetrain followed by an immediate loss of motive power (Limp Mode) in my new 2026 Toyota 4Runner TRD Pro. The engine revved significantly, but the vehicle failed to accelerate as intended, creating a hazardous situation in the intersection of oncoming traffic. A diagnostic health check at an authorized dealer confirmed stored DTC fault codes P281671 and P08BA71, indicating that Pressure Control Solenoids Actuators "H" and "L" were in a "stuck" state. The vehicle's Freeze Frame Data recorded a catastrophic internal transmission slip, showing an engine speed of 1767 RPM while the vehicle was moving at only 4 MPH in 2nd gear. There are no previous warning signs or symptoms of this problem before the transmission failure. It was sudden and unexpected. The manufacturer’s technical service protocols (such as T-SB-0094-24/T-SB-0076-24) for these specific solenoid codes on this specific 8-speed hybrid transmission (L580F) – which is equipped on my vehicle – identify this as an internal mechanical actuator failure requiring full transmission, torque converter, and hybrid module replacement. However, the manufacturer has denied the repair because the vehicle’s specific VIN is not yet listed on a service bulletin and that they could not reproduce it in a short test drive. The manufacturer’s official recommendation is to continue operating the vehicle with a documented and non-repaired powertrain defect until a second failure occurs in traffic. I am reporting this as a significant safety risk, as a recurring loss of motive power during critical driving maneuvers puts myself and other motorists in danger. The vehicle and its stored diagnostic data are available for inspection.
The car has the iforce max powertrain. At low speeds or in stop and go traffic, when the car has come to a stop, the car will lurch forward, which could potentially cause an accident. I took car to dealership and they said this is normal operation of the hybrid system and there is no fix. This is a huge safety issue if the car pushes itself forward and potentially causing an accident. The transmission system is very unrefined.
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 25, 2026