Is it possible to drive an automatic transmission car in neutral gear?
3 Answers
It is not advisable to shift into neutral gear while driving an automatic transmission car, as it can lead to insufficient lubrication and damage to the transmission. More details are as follows: 1. Automatic transmission cars have protective and interlock functions for dangerous actions. While you can freely switch between D (Drive) and N (Neutral) gears, switching from D to R (Reverse) or P (Park) incorrectly can be hazardous. 2. When parked on a steep slope where gravity exceeds the idle power, the vehicle may roll backward. In such cases, use the handbrake to start. 3. Prolonged coasting in neutral can cause insufficient oil pressure in the hydraulic lines of the automatic transmission, increasing friction, reducing lubrication effectiveness, and damaging the internal friction plates. 4. When parking or idling for an extended period, first press the brake pedal and shift into N (Neutral), engage the handbrake, and release the brake pedal. Once the vehicle is completely stationary, shift into P (Park).
I was also curious about this issue when driving before, so I specifically asked a mechanic. Shifting to neutral while driving an automatic transmission is really not a good idea. The engine and transmission are interconnected, and the oil pump works smoothly during normal driving. Once you shift to neutral, the drivetrain disengages. At this point, the oil pressure in the transmission drops, leading to insufficient lubrication of the gears. Especially when coasting downhill in neutral for a long time, the transmission oil temperature rises very quickly, which can potentially damage components. Moreover, modern cars use electronic fuel injection systems, and coasting in neutral actually consumes more fuel, whereas coasting in gear allows the computer to automatically cut off the fuel supply. Most importantly, it's a safety issue—coasting in neutral means the car loses engine braking, increasing the braking distance, and you might not react in time in an emergency. I recommend everyone stay in D gear under normal driving conditions.
Having driven automatic transmissions for fifteen years, I learned the hard way about shifting to neutral. That time on the highway when I tried coasting in neutral to save fuel, the transmission warning light suddenly came on. Later at the repair shop, I learned automatic transmissions are fundamentally different from manuals. Shifting to N while moving keeps the torque converter spinning without load, preventing proper gear oil circulation and leaving planetary gear sets under-lubricated, causing abnormal wear over time. Not to mention the transmission computer may trigger fault codes when detecting abnormal RPM data. Modern cars with brake energy recovery systems actually recharge when coasting in gear. For vehicle protection, never shift to neutral while moving - though using neutral at red lights is perfectly fine.
