Should You Shift to Neutral When Waiting at a Red Light?
2 Answers
For automatic transmission vehicles, whether to shift to neutral during brief stops at red lights or when parking depends on the duration of the stop. For short stops, it's not necessary to shift to neutral. However, for prolonged stops, shifting to neutral is advisable. For waits exceeding 30 seconds, it's recommended to shift to neutral and engage the handbrake. Below is additional information on other gear positions: 1. P (Park) Gear: The P gear is for parking and can be engaged directly without pressing the brake or pulling the handbrake. However, since engaging P gear requires passing through R (Reverse) gear, it can cause some impact on the transmission, although this impact is generally minor. Additionally, in the event of a rear-end collision while waiting at a red light, having the car in P gear could damage the transmission. Therefore, using P gear in such situations is not recommended. 2. D (Drive) Gear: If the stop is very brief, staying in D gear is acceptable. However, for longer stops, it's best to avoid keeping the car in D gear. When the gear selector is in the drive position, automatic transmission vehicles tend to have a slight creeping motion. Continuously holding the brake to counteract this motion can cause the transmission fluid temperature to rise, leading to fluid degradation. This is particularly detrimental when the air conditioning is on and the engine is idling at a higher speed. 3. N (Neutral) Gear: When the gear selector is in N gear, the power connection between the engine and the transmission is disconnected. This is suitable for brief stops, such as waiting at a red light. To prevent the vehicle from rolling on an incline, it's advisable to press the brake or engage the handbrake.
I've always been curious about whether to shift into neutral at red lights. When driving a manual transmission car, I'm used to shifting into neutral to save fuel, because keeping it in gear consumes more fuel during idle, especially during long waits at lights. However, with an automatic transmission, it's fine to stay in D (Drive) and hold the brake—shifting into neutral might not save fuel and could instead increase vibrations from gear switching. Modern cars even have auto start-stop systems that automatically shut off the engine at stops and restart when the light turns green, which is super convenient. I've looked into some information, and shifting into neutral at frequently stopping intersections can reduce clutch wear, but it has little effect on fuel consumption. The suggestion is to decide based on the type of car and personal habits—the key is not to let your foot get tired and affect driving safety.
