Which gear should an automatic transmission be in when stopping at a red light?
4 Answers
When stopping at a red light with an automatic transmission, the specific gear to use depends on the duration of the red light. The gear selection options are as follows: 1. If the red light is less than 30 seconds, it is recommended that the driver simply keep their foot on the brake; 2. If the red light lasts between 30 seconds and 1 minute, the driver should shift to N (Neutral) gear and engage the handbrake; 3. For red lights longer than one minute, it is advisable to shift directly to P (Park) gear and engage the handbrake. Apart from waiting at traffic lights, automatic transmission vehicles may also need to be parked with the engine off or left idling for extended periods. In such cases, the gear should be shifted to P (Park) because engaging P gear causes the transmission's parking pawl to lock into the parking gear, securing the vehicle's drivetrain. The correct parking procedure is: first, press the brake pedal and shift to N (Neutral) gear, then engage the handbrake and release the brake pedal. Once the vehicle is completely stationary, shift to P (Park) gear.
As a driver with years of experience, I find it most convenient to stay in D gear when stopping at a red light. Just keep your foot on the brake, and when the light turns green, release the brake and go—smooth and quick. For longer stops, like over a minute or when waiting for a train, I switch to N gear to give my foot a break and pull the handbrake to save effort. Never shift to P gear, as it locks the transmission system. If you get rear-ended, it can damage the car, and unlocking it slows down your start, delaying traffic. My old car has over 100,000 kilometers on it, and I've always operated it this way—the transmission and brake systems are still durable. Safety first—always be prepared to avoid panicking in sudden situations.
When waiting at a red light in an automatic transmission car, I prefer to stay in D gear while pressing the brake. The internal clutch in the transmission will automatically disengage, reducing mechanical wear, eliminating the need for frequent manual gear shifting. If the red light lasts longer, shifting to N gear can slightly reduce engine load and save a bit of fuel, but actual tests show minimal difference—only about a few thousandths in fuel consumption variation. Engaging P gear is not advisable as it fully locks the transmission, causing response delays and adding unnecessary wear risks. Some modern cars are equipped with auto start-stop functions, allowing the engine to pause while in D gear, making it more intelligent and energy-efficient. The key is to protect components from a mechanical perspective and minimize unnecessary operations, ensuring longer vehicle lifespan and smoother, more stable driving.
For environmental protection and energy saving, I'm used to shifting to N gear when stopping at a red light. The engine load is reduced, and the idling fuel consumption is slightly less. Although the amount is small, it adds up meaningfully. It's also acceptable to stay in D gear during short stops, but it slightly wears the clutch plates. Through practice, I've found that shifting to N gear makes the car quieter and more comfortable for my feet. As long as I press the brake properly without compromising safety, it's fine. Every bit of fuel saved contributes to reducing emissions, and small actions matter.
