What Causes the Noise When Pressing the Brake in P Gear?

[Damian]

p> The noise when pressing the brake in P gear is caused by rust on the brake disc or brake pads, or new brake pads. The specific reasons are as follows: Rust on the brake disc or brake pads: After parking for a long time, especially in humid weather or after rain, some rust or dirt may appear on the brake disc or brake pads. This issue can usually be resolved by driving for a while, or by applying butter or special lubricating oil to the connection between the brake pads and the brake caliper. New brake pads: A similar noise may occur when pressing the brakes in a new car. If it's a new car or the brake pads have just been replaced, the new brake pads and brake disc need a break-in period. This noise is completely normal during this process.

[SanLorenzo]

My own car also makes this sound. I remember last time in the parking lot, when I pressed the brake to shift gears, there was always a clicking noise that startled me. Later, I asked a friend and learned that this is a normal design. The P (Park) position has a locking mechanism, and when you press the brake, it releases a small locking pin, allowing you to shift from P to R (Reverse) or D (Drive). The sound is like mechanical components moving. Most of the time, it's crisp, like a light tap from a wrench, and nothing to worry about. However, if the sound becomes unusually loud, continuous, or accompanied by a sticking sensation, it might indicate a worn-out locking pin or insufficient lubrication. If ignored for a long time, the car might get stuck in P and fail to shift, which would be troublesome. In such cases, I always listen carefully to locate the sound and ensure the brake lights are on, as functioning lights confirm the brake signal is reaching the transmission. Safety first—occasional sounds are nothing to worry about, but if it’s abnormal, visit a repair shop promptly.

[VanMiguel]

Every time I drive my dad's old car, there's this crisp clicking sound when I shift to P mode and step on the brake, which is quite interesting. This is actually the P mode locking mechanism at work. Simply put, there's a small component in the transmission called the lock pin. When you press the brake, it releases, allowing the gear lever to move. The sound is normal, like a door latch clicking, but if it turns into a whining or continuous squeaking, there might be an issue, such as internal gear wear or debris getting stuck. Applying too much brake force might also interact with the internal parts of the transmission, causing strange noises. I've tried it multiple times myself—the sound is usually quieter at normal temperatures, but it might be more noticeable during cold starts in winter due to insufficient lubrication. If the car is still under warranty, I recommend taking it directly to the dealership for a mechanic to check, to avoid causing damage by tinkering yourself. Regular maintenance of the transmission fluid can help reduce these odd noises.

[SanJames]

When my child was learning to drive, they were always worried if the sound of stepping on the brake in P mode could be dangerous, so I explained that it's a normal phenomenon. The sound mostly comes from the transmission lock mechanism, which is designed for safety to prevent accidental gear shifting—it only unlocks when you step on the brake. Normally, the sound is slight and not bothersome. However, if it becomes louder or the gear lever shakes with noise after braking, it might lead to difficulty in shifting gears or even getting stuck, which is very dangerous for new drivers. I told them to always check if the sound is consistent and that the brake lights are on, as this confirms the signal is working properly. If there’s occasional difficulty in shifting gears or unusual smells, don’t ignore it—take the car to a shop immediately to check for electrical or mechanical issues. In short, just stay alert to these signs, and don’t let small issues turn into big problems.