Should You Shift to Neutral at a Red Light in an Automatic Transmission Car?

[VanPhoebe]

Whether to shift to neutral at a red light in an automatic transmission car depends on different situations: 1. Shift to neutral if the red light lasts more than 30 seconds; 2. Simply press the brake if the red light lasts less than 30 seconds. An automatic transmission refers to a system where the driver does not need to manually shift gears; the vehicle automatically selects the appropriate gear based on driving speed and traffic conditions. Precautions for shifting gears in an automatic transmission car: 1. Do not press the accelerator pedal when shifting gears; 2. Do not immediately press the accelerator pedal hard after shifting gears; 3. The vehicle can only be started in P or N gear; 4. To move the gear lever out of P, the brake must be pressed; 5. Do not shift into N gear while driving to coast; 6. Do not push into P gear while the vehicle is moving; 7. When changing the direction of travel, switching between D and R gears should only be done after the vehicle has come to a complete stop; 8. Placing the gear in N while driving prevents the oil pump from supplying oil normally for lubrication, which can cause the internal components of the transmission to overheat and result in damage.

[CameronMarie]

Having driven automatic transmission cars for over a decade, whether to shift to neutral at red lights depends on the situation. For short stops, I just keep my foot on the brake while remaining in D gear—the soft connection between engine and transmission won't harm the car. For long red lights exceeding 60 seconds, I shift to N and engage the handbrake, giving my right foot a rest while slightly reducing transmission fluid temperature. However, frequent gear changes actually wear out the shift mechanism, so in urban areas with closely spaced traffic lights, I generally avoid shifting. Many modern cars now feature AUTOHOLD functionality which makes this even easier—a firm brake press activates auto-hold, and you can just press the accelerator to go when the light turns green.

[EmmettFitz]

As a long-distance driver, I don't think it's necessary to shift to neutral at red lights for automatic transmissions. Modern transmissions keep the torque converter in a slipping state when braking in D gear without hard engagement, making wear negligible. Shifting to N gear repeatedly is not only troublesome but also makes acceleration slower when shifting back to D. I've calculated fuel consumption before, and the tiny amount of fuel saved by shifting to neutral isn't even worth a bottle of mineral water. What's more important is to avoid using P gear at red lights - if rear-ended, the transmission gears could be completely destroyed.

[AutumnRose]

When teaching driving, I noticed students often struggle with this. My advice is to check the red light duration: if it's shorter than 30 seconds, stay in D gear with the brake pressed; if it exceeds 1 minute, shift to N gear and engage the handbrake to reduce transmission strain. However, modern cars with auto start-stop systems are more convenient - the engine shuts off automatically when stopping and restarts when pressing the accelerator, eliminating gear changes. The key point: never wait at lights in N gear on slopes - you'll be fully liable if the car rolls and causes a rear-end collision.

[MacDominic]

The experienced transmission mechanic told me that putting an old 4AT car in neutral can indeed lower oil temperature, but it's completely unnecessary for newer models. I once tested it - keeping the car in D with brakes on only consumes 0.15L more fuel per 100km compared to neutral. The real danger is forgetting to engage the handbrake or step on the brake after shifting to neutral, risking rollback on slopes. With AUTOHOLD system, this isn't a concern - a firm brake press automatically engages parking.