Can automatic transmission cars coast in neutral? Does it save fuel?
3 Answers
Automatic transmission cars should not coast in neutral for extended periods, as this operation not only fails to save fuel but also damages the transmission. Automatic transmission gear shifting: The transmission of an automatic car is completely different from that of a manual car. The gears of an automatic car are shifted by the onboard computer based on throttle response or preset vehicle speed. If you attempt to save fuel by shifting from D (Drive) to N (Neutral) while driving, the mismatch between the vehicle's speed and the transmission's speed can cause insufficient oil pressure in the hydraulic supply lines inside the transmission. This increases friction within the transmission, reduces lubrication effectiveness, and ultimately damages the friction plates inside the transmission. Fuel-saving practices for automatic cars: In fact, the most fuel-efficient operation for an automatic transmission car is to coast with the D (Drive) gear engaged. Allowing the engine to keep the transmission gears rotating synchronously while coasting is the correct approach.
I used to wonder about coasting in neutral when driving an automatic car and tried it a few times, but it didn't feel right. Technically, you can shift to neutral to let the car coast, but it's very unsafe. For example, when going downhill, losing engine braking makes it harder to control the brakes, increasing the risk of accidents. Additionally, automatic transmissions rely on oil pressure to lubricate components, and coasting can lead to insufficient lubrication, potentially causing internal wear. As for fuel savings, modern cars don't recommend coasting at all: when coasting in gear, the engine automatically cuts fuel, saving more gas; in neutral, the engine still idles, which actually consumes more fuel. I suggest not risking it to save a little fuel—driving smoothly in D is much safer. Developing fuel-efficient habits like avoiding sudden acceleration and maintaining a steady speed is better for both your car's condition and your wallet.
As an average car owner who loves to experiment, I once tried coasting in neutral thinking it would save fuel. Honestly, the results were disappointing: the car could coast but felt unstable and unsafe, especially when changing lanes—it made me nervous. After researching, I learned that automatic transmissions aren’t designed for prolonged neutral use, as it can cause lubrication issues and lead to costly repairs. Does it save fuel? Modern cars actually cut fuel supply more efficiently when decelerating in Drive (D), while Neutral (N) forces the engine to idle and waste gas. My neighbor, who drives an old car, claims coasting might save fuel—but that’s for carburetor-era relics. Nowadays, with fuel injection being standard, it’s not worth copying. Bottom line: don’t recklessly shift to neutral while driving; safety and cost-efficiency matter more. Proper gear usage and regular tire pressure checks are far better ways to save fuel.
