Should You Shift to P or N When Stopping at a Red Light with an Automatic Transmission?
3 Answers
When stopping at a red light with an automatic transmission, you should shift to N gear. Here are the specific reasons: 1. If the wait is more than 30 seconds but less than a minute, shift to N gear and engage the handbrake. This allows you to release your right foot for a rest, disconnects the power transmission, reduces engine load, decreases fuel consumption, and is also very safe. 2. It is not recommended to shift to P gear when waiting at a red light because when the vehicle is in P gear while stopped at a red light, a hook in the transmission will latch onto the gear, causing mutual force between them. Over time, this can accelerate transmission wear. Here are some precautions for stopping and turning off the engine with an automatic transmission: 1. When turning off the engine or idling for an extended period, an automatic transmission car should be shifted into P gear. This is because shifting into P gear causes the parking pawl in the transmission to engage with the parking gear, locking the car's drivetrain. 2. The correct way to stop is to first press the brake pedal, shift into N gear, then engage the handbrake and release the brake pedal. Once the vehicle is completely stopped, shift into P gear.
I've been driving an automatic transmission car in the city for commuting for over a decade, and I've developed the habit of shifting to N (Neutral) gear when waiting at red lights during daily driving. The reason is quite simple: while P (Park) gear is indeed for parking, it locks a component in the transmission called the parking pawl. If you get rear-ended while waiting at a red light, this pawl might deform or get damaged upon impact, and repairs can be costly. Shifting to N gear avoids this issue—the car won't roll on flat ground as long as you keep the brake pedal pressed, and it also reduces stress on the transmission and engine. Especially at busy intersections with frequent light changes, using N gear is more convenient; you can smoothly shift to D (Drive) gear and start moving as soon as the light turns green. Additionally, I've noticed that using N gear saves more fuel compared to keeping it in D gear while holding the brake, as the transmission isn't fighting against the load. Of course, if the red light is very brief, you can stay in D gear, but making a habit of shifting to N gear is more car-friendly and helps avoid unnecessary wear.
From a car maintenance perspective, I recommend shifting to Neutral (N) gear rather than Park (P) gear when waiting at red lights. The P gear is suitable for long-term parking or complete engine shutdown, as it locks the wheels with the parking mechanism. However, using P gear while temporarily stopping at red lights poses significant risks; if rear-ended, the impact force directly affects the transmission internals, potentially causing severe damage or even requiring a full replacement. Shifting to N gear keeps the transmission in a free state without load, reducing wear and fuel consumption. I've seen some drivers habitually use P gear, which actually harms the vehicle's drivetrain, especially in urban stop-and-go scenarios. The N gear operation is simple, allows quick gear changes, and gives your foot a rest. For slightly longer red lights, you can combine it with the handbrake for added stability. In summary, using N gear during daily driving extends transmission lifespan and saves some fuel costs.
