Which gear should an automatic car be in when waiting at a red light?
2 Answers
If the waiting time is more than 40 seconds, shift to N gear and apply the handbrake. For less than 40 seconds, simply keep your foot on the brake in D gear. Here are some additional details about automatic transmission cars: 1. Heavy traffic: In cases of severe traffic congestion, it is recommended to shift to P gear. For brief stops, you can shift to N gear and apply the brake, depending on the situation. 2. Working principle: Automatic transmission cars typically use a hydraulic transmission device to replace the mechanical clutch found in manual transmission cars, hence there is no clutch pedal. When the engine speed is low, the torque transmitted by the fluid is limited and insufficient to move the car forward. When the gear lever is moved to the drive position and the brake pedal is released, increasing the throttle and engine speed raises the transmitted torque, propelling the car forward.
When waiting at a red light, I choose between putting the car in N gear or keeping it in D gear while pressing the brake. It depends on the duration of the red light and road conditions. For short red lights, keeping it in D gear and pressing the brake is the most convenient—quick to start, no need to shift back and forth, which is ideal for city traffic congestion. However, for longer waits, such as over 30 seconds, I shift to N gear to reduce the burden on the brakes, give the transmission a rest, and prevent overheating or premature wear. Additionally, from a safety perspective: although P gear locks the car, if a rear-end collision occurs, it could damage the transmission, so N gear carries relatively less risk. Of course, if you keep pressing the brake in D gear for too long, your leg may get tired, making N gear a more relaxed option. Overall, most drivers are accustomed to pressing the brake in D gear, but developing the habit of switching based on timing can make driving more comfortable and efficient.
