Should You Shift to P or N Gear at a Red Light with an Automatic Transmission?
2 Answers
When waiting at a red light with an automatic transmission car, you can shift into N gear or keep it in D gear while stepping on the brake, but you should never shift into P gear. Using P gear at a red light is not recommended. Although both P gear and N gear can be used when parking, they are not the same, and their usage scenarios are also different. Here are some relevant details: 1. After shifting into P gear, the automatic transmission has a locking mechanism that locks the gears, which indirectly locks the wheels. Even without engaging the handbrake, the car cannot move after shifting into P gear. However, after shifting into N gear, there is no locking mechanism in the automatic transmission to lock the gears, so the car can move if the handbrake is not engaged. 2. P gear is used when parking and turning off the engine, while N gear is used for short stops without turning off the engine. If you shift into P gear at a red light and get rear-ended by another vehicle, your car's transmission could suffer severe damage.
When I drive, I shift to N (Neutral) gear and engage the handbrake whenever I stop at a red light for more than half a minute. The P (Park) gear is designed for parking, and while it might be fine for long-term use, if a rear-end collision occurs during a short stop at a red light, the locked transmission in P gear could cause internal damage, leading to costly repairs. Shifting to N gear keeps the car in a neutral state, eliminating this risk while also reducing engine load and saving a bit of fuel. I’ve developed this habit over years of driving in busy downtown areas, and it’s both safe and practical. I remember one time during heavy rain when another driver left their car in P gear and got rear-ended—the repair cost over a thousand dollars, a harsh lesson. For short red lights (under 10 seconds), staying in D (Drive) gear is fine, but for longer stops, switching gears offers better protection at a reasonable cost.
