Will the car roll when parked in P gear?
3 Answers
The car will not roll when parked in P gear without engaging the handbrake, but it is recommended to engage the handbrake, otherwise it will cause excessive force on the P gear locking mechanism, which will reduce the service life of the P gear locking mechanism. P gear: parking means "parking". Parking gear or parking gear, used when parking. When you reach your destination or need to park for a long time, shift the gear lever into this gear. Note: You must shift into P gear only after the vehicle has come to a complete stop. Shifting into P gear before the vehicle has completely stopped may cause damage to some mechanical parts of the automatic transmission. When shifting into P gear, the wheels are mechanically locked, which can prevent the vehicle from moving forward or backward, so it is necessary to shift into P gear when parking on a slope. In addition, during short stops (such as waiting at a traffic light), it is best not to shift into P gear to prevent being rear-ended by a following vehicle, which could cause severe damage to the entire transmission. In addition, automatic transmission cars are also divided into R, N, S, M, L, D and other letter gears. Different gear combinations output different power. When the car is at different speeds, it is necessary to "shift gears", that is, to select different gear combinations to output power. The following is a detailed introduction: R gear: reverse means "reverse". Whether it is a manual transmission or an automatic transmission, R is the reverse gear. Shift into R gear, and the car will move backward. This gear can only be engaged when the vehicle is stationary and the engine is idling. Never use R gear when the vehicle is moving forward, and pay special attention to the control of the accelerator pedal when reversing. N gear: Neutral means "neutral", also called neutral gear. When waiting at a traffic light, you can shift into this gear and step on the brake. If you need to wait for a long time, it is recommended to directly engage the handbrake, and then you can take your foot off the brake pedal to rest. Many people also have a misconception that shifting into N gear when coasting downhill or at high speed can save fuel. In fact, this is a serious mistake. Doing so not only does not save fuel but can also damage the transmission. S gear: Sport means "sport" and refers to the sport mode in a car. When shifting into this gear, the gear shift time will be delayed to provide more power, generally used when overtaking. M gear: manual means "manual control" and refers to switching to manual mode in a car, operating the same as a manual transmission car, requiring manual gear shifting. L gear: Low means "low speed" and refers to the low-speed forward gear in a car. When shifting into this gear, the transmission can only work in low gear (equivalent to the 1st gear in a manual transmission) and will not automatically switch to other gears due to speed changes. This gear is generally used when climbing or descending a slope. In low gear, the driving wheels output greater torque, providing sufficient power to climb steep slopes. Prolonged braking can cause the brake pads to overheat and reduce braking effectiveness, which is very dangerous on long or steep descents. In this case, you can shift into L gear to use the engine's low speed to restrain the vehicle's movement, and the driver does not need to keep stepping on the brake. D gear: Drive means "drive". Shift into this gear, step on the accelerator, and the vehicle can move. In this gear, the transmission will automatically shift according to the speed and accelerator conditions. When waiting at a traffic light, you can stay in D gear and step on the brake. If the waiting time is short, there is no problem with this, but if the time is long, it will cause the transmission oil temperature to rise and the oil to deteriorate.
To be honest, I was also worried about the car rolling in P gear before, especially when parked on a slope. The P gear actually has a small pawl inside the transmission that locks the gear, but it mainly prevents pushing rather than relying entirely on friction to stop the car. I've seen many drivers get out of the car directly after shifting to P gear, and the car moves slightly before locking, which is quite common with that slight movement and clunking sound. If the slope is steep, relying solely on the P gear to hold the gear does put a lot of pressure on it, and metal parts can deform over time. I recommend everyone develop the habit of straightening the wheels before stepping on the brake and shifting to P gear. On slopes, after stopping, pull the handbrake tight first and then shift to P gear, so the pressure on the gear is much less. If the car does roll one day, quickly use a stone to block the tire as an emergency measure.
From the transmission repair cases I've encountered, the P (Park) gear was originally designed to prevent movement rather than actively brake. Its locking pawl is prone to overload on slopes. Consistently engaging P gear directly when parking on steep inclines may cause pawl deformation or even gear tooth damage. During one disassembly of a faulty transmission, I noticed obvious wear and dents on the locking teeth of a vehicle frequently parked on steep slopes. While slight inclines on urban roads might be barely noticeable, continuous lateral force can still cause uneven internal stress distribution. The correct procedure should be: bring the vehicle to a complete stop → firmly depress the foot brake → shift to neutral (N) → engage the parking brake → release the foot brake to confirm no movement → finally shift to P gear. This allows the braking system to share the mechanical load.
