Nissan Leaf gearbox issues often involve the single-speed reduction gearbox, with common problems like differential wear, grinding noises, rough shifts, or the shifter getting stuck, sometimes due to internal wear or low/old fluid (Nissan Matic S ATF). While battery degradation and power inverter failure are more known, gearbox oil changes (around every 30k miles or sooner) and careful driving (avoiding constant max torque) can prolong its life, but serious issues may need professional diagnosti