Should You Shift to Neutral at Red Lights with an Automatic Transmission?
4 Answers
When waiting at a red light with an automatic transmission car, you can shift to neutral (N), and if the wait is prolonged, you can also engage the handbrake. Below is an introduction to gear selection while waiting at red lights: Duration for shifting to N gear at red lights: When waiting at a red light, briefly shifting to N gear is generally fine, but leaving it in N gear for extended periods can harm the vehicle, especially the transmission. Keeping the car in D gear while braking at a red light is akin to pressing both the accelerator and brake simultaneously in a manual transmission car. In this scenario, fuel consumption increases, and over time, the torque converter remains under stress for prolonged periods, accelerating wear on components like the torque converter. Avoid shifting to P gear at red lights: You should not shift to P gear while waiting at a red light because engaging P gear without the handbrake can damage certain components; starting from P gear involves cumbersome steps; frequently shifting to P gear can cause gear grinding in the automatic transmission, damaging its bearings. The correct approach is to shift to N gear while braking; when the light turns green, shift to D gear and proceed.
After driving automatic transmission cars for decades, I've found that in most cases, there's no need to shift to neutral when waiting at red lights. Back in the days of older cars, instructors often said putting it in neutral could save some fuel and reduce transmission stress. But with today's automotive technology advancements, shifting to neutral might actually slow down your start. For instance, when the light suddenly turns green or when a car is approaching from behind, starting directly from D with brake pedal pressed is quicker. Modern cars' idle systems are designed quite efficiently – short waits in D gear won't significantly increase fuel consumption or damage the vehicle. Of course, for exceptionally long red lights (say over 1-2 minutes), occasionally shifting to neutral to rest your foot is fine, but I always prioritize safety and convenience. In summary, just keeping it in D with brake pressed during daily driving is simple and worry-free.
When I first learned to drive an automatic car, I was quite confused about shifting to neutral at red lights. My driving instructor advised against it, saying that in case of sudden situations, like an electric scooter darting out or the light turning green early, shifting from N to D would cause a delay, increasing the risk. After driving for a while myself, I also found it more comfortable to stay in D and keep the brake pressed. For longer red lights, shifting to neutral might save a tiny bit of fuel, but modern engines consume very little at idle, so the effect is negligible. Additionally, frequent gear shifts could wear out components, causing more trouble. I suggest beginners not overthink it—just follow the flow of traffic. Safety first is more important than saving a little fuel, and relaxed driving is the way to go.
As a car enthusiast, I must say whether to shift to neutral at red lights with an automatic transmission depends on transmission principles. When in D gear with brakes engaged, the torque converter keeps rotating but with minimal load, maintaining engine idle. Shifting to N gear disconnects the engine, slightly improving fuel efficiency by reducing power loss, but requires time to reconnect the powertrain upon restart. Modern vehicles have optimized idle control - staying in D gear is more efficient for short red lights; N gear for prolonged stops helps mitigate heat buildup. The key is avoiding frequent gear shifts to minimize potential wear. Based on vehicle design, simply waiting in D gear is more straightforward and efficient.
