Should I Shift to P Gear Before or After Turning Off the Engine?

[MacJuliana]

Both methods—turning off the engine before shifting to P gear or shifting to P gear before turning off the engine—are correct and will not cause any damage to the vehicle. Modern car transmissions are equipped with two sets of gears: one for driving and shifting, and the other for parking and locking. When parking, as long as the vehicle is stationary, the locking gears are not engaged, and the driving gears are inactive. The P (Park) gear works by using a mechanical device to lock the rotating parts of the car, preventing it from moving. For long-term parking, it is essential to firmly engage the handbrake and shift the gear to P.

[MaliaFitz]

Last time I specifically consulted a veteran mechanic at the 4S店 about this issue. He asked me to imagine the gear latch in the transmission. If you shift to P挡 before turning off the engine when parking, all the impact force from vehicle movement will be entirely borne by the transmission. My habit is: brake to a complete stop → shift to N挡 → engage the handbrake → release the foot brake to let the car settle naturally → finally press the brake and shift to P挡 before turning off the engine. This way, the handbrake takes the initial force, protecting the transmission gears. However, the old technician said that occasionally getting the sequence wrong is no big deal—transmissions aren’t that fragile—but developing good habits can extend their lifespan. This procedure is especially important when parking on slopes. Once, I forgot to engage the handbrake on a mall ramp and shifted directly to P挡; when restarting, the transmission made a loud 'clunk' noise that scared me half to death.

[SanSophia]

Haha, I've tried two approaches to this issue! When I first started driving an automatic, I often forgot the sequence. Once, in a hurry to get something done by the roadside, I directly shifted to P and turned off the engine, only to find the gear lever stuck solid the next time I started the car. Later, after reading the manual, I understood the principle: the P gear's locking hook engages with the transmission gear slot. My suggestion is to first firmly engage the handbrake before shifting to P, allowing the braking system to share the pressure. Once, while assisting as a driving instructor, I witnessed a student shift to P without engaging the handbrake, causing the car to roll and snap the transmission's locking hook, resulting in a repair bill over three thousand. Now, my operating mantra is 'Stop firmly, pull the handbrake, shift gears, then turn off,' and after eight years, the transmission still operates smoothly.

[StHaven]

As a mechanical engineering professional, I'm accustomed to explaining this matter using physical principles. The P gear is essentially a mechanical lock, with all vehicle inertia impact acting on the transmission gears. Recommended sequence: press brake to stop completely → shift to neutral → engage electronic parking brake → release foot brake to confirm vehicle is fully stationary → finally shift to P gear and turn off engine. Never shift to P gear at red lights - a rear-end collision could directly destroy the transmission. Last time a colleague's Mercedes was hit while waiting at a red light in P gear, the dealership said the transmission housing cracked and needed complete replacement. By the way, cars with auto-hold function are simpler - just press the brake firmly to activate AUTOHOLD and turn off the engine directly, the system will automatically shift to P gear.

[MacMackenzie]

My wife also struggled with this issue when she was getting her driver's license, and I noticed that driving schools teach different methods when practicing with her. After driving our family's CR-V for three years, I've figured out that on flat roads, it's fine to directly press the brake, shift to P, and turn off the engine. But on slopes, you must strictly follow the steps! Last week, when parking on the slope in our underground garage, I turned off the engine before shifting to P, and the car rolled back half a meter, hitting the guardrail. The mechanic later told me the correct procedure: brake to a complete stop → shift to N → firmly pull the handbrake → release the brake to confirm no rolling → finally shift to P and turn off the engine. Now, every time I park on a slope, I count the steps as I do them, and there haven't been any problems since.

[DelJuliette]

When I first bought my Tesla, I did some research too. For traditional fuel-powered cars, it's recommended to engage the handbrake before shifting to P (Park), the principle being to avoid putting stress on the transmission's parking pawl. But with electric vehicles, it's simpler: come to a complete stop by braking, press the P button directly, at which point the electronic parking brake will automatically engage, then you can power off and exit the vehicle. Once, while driving a friend's Audi Q5, I noticed a 'click' sound when shifting to P, which is the sound of the parking gear engaging. A mechanic mentioned that if you frequently shift directly to P on slopes, this locking mechanism can wear excessively, potentially causing abnormal noises when shifting after 50,000 kilometers. Now, with fuel-powered cars, I strictly follow the five-step routine: 'brake → shift to N (Neutral) → engage handbrake → release footbrake → shift to P and power off'.