Which gear should an automatic car be in when waiting at a red light?

[Philip]

When waiting at a traffic light in an automatic car, if the expected wait time is within 20 seconds, you can use D gear along with the foot brake. For situations with traffic congestion where the wait exceeds 30 seconds, shift to N gear and engage the handbrake. Below is relevant information about the N gear in cars: Main purpose: In automatic transmission models, engaging N gear creates a power interruption effect similar to shifting to neutral in manual transmissions, though there are some differences. Precautions: Automatic cars should not coast in neutral under non-special circumstances, as it is not only unsafe but can also lead to transmission failure due to insufficient lubrication of gears and other components caused by inadequate oil supply from the transmission oil pump.

[DeCecilia]

I've been driving automatic transmission cars for almost ten years. When it comes to which gear to use at red lights, let's talk from a safety perspective. If the stop is brief, like just a few seconds, I usually stay in D gear while holding the brake, so I can start moving immediately when the light turns green without blocking traffic behind me. But for long red lights, say over 30 seconds, I recommend shifting to N gear and engaging the handbrake. This gives your foot a rest and protects the transmission – if you get rear-ended while in D or P gear, it could damage the gears, whereas N gear is relatively safer. Also, remember to keep your brake lights on so following drivers can see you're stopped, reducing accident risks. In summary, be flexible based on the stop duration – don't always rigidly use P gear.

[Ronald]

From a fuel-saving perspective, it's best to shift an automatic transmission car into N (neutral) gear when waiting at a red light. I used to keep it in D (drive) gear, but found that fuel consumption increases slightly at idle because the engine continues to drive the transmission—it feels like the car is straining, wasting more fuel. Shifting to N gear lightens the engine load, making idle smoother and benefiting the engine in the long run by reducing wear. Especially in city traffic with frequent minute-long red lights, shifting to N and engaging the handbrake saves fuel costs and is more eco-friendly. Some argue that staying in D and holding the brake is fine, but my tests show it's acceptable briefly; prolonged use makes the fuel gauge drop faster. A simple gear shift brings multiple benefits.

[OJosiah]

I usually drive an automatic transmission for commuting, and at red lights, I just keep it in D gear without shifting. Switching to N gear means having to shift back to start, which is too much hassle, especially for short red lights lasting just a few seconds—you can go as soon as the light turns green, saving trouble. When in D gear, just hold the brake, and the car will stay firmly in place without rolling. Some people worry about transmission wear, but my car has been fine for five years. Car manufacturers have already considered this, so short waits are no problem. Just remember not to shift into P gear—if someone bumps your rear bumper, the gears could lock up. In short, convenience comes first—don’t overcomplicate it.

[LeSamantha]

As someone who frequently takes kids out, during long red lights, I shift to N gear and engage the handbrake, allowing my foot to rest off the brake pedal comfortably. Keeping it in D gear with constant braking tires my foot over time, and the car may have slight vibrations, disturbing the child's sleep. Shifting to N gear reduces transmission stress, operates quietly, and keeps the cabin noise-free. I've tried P gear a few times but found it too cumbersome for quick starts and impractical in emergencies. For short red lights, I stay in D gear with the brake pressed, but for anything over 15 seconds, I definitely switch to N gear. Developing this habit makes driving much more relaxed.

[SanFrank]

When waiting at a red light, gear selection should consider vehicle maintenance. Having repaired many cars, I recommend using N (Neutral) gear as the most appropriate choice. Keeping the car in D (Drive) gear maintains transmission engagement, forcing the engine to drag the vehicle, which may increase wear and potentially damage components over time. Using P (Park) gear risks transmission destruction if rear-ended. Shifting to N gear with the handbrake engaged protects mechanical components while preventing accidents. Many modern vehicles feature auto start-stop systems that shut off the engine at red lights - in this case, both D and N gears function similarly as the system manages operation. Ultimately, adapting gear selection based on traffic light duration extends vehicle lifespan while ensuring safety.