Is it necessary to press the brake when shifting from S to D gear?

[SanHannah]

Shifting from S to D gear does not require pressing the brake. Below are some relevant introductions about automatic transmissions: 1. Shifting from P to any gear requires pressing the brake: This is a safety feature to ensure driving safety. Otherwise, the moment you shift from P to R or D, the car will immediately have a driving force backward or forward, and the handbrake alone may not be sufficient to stabilize the car, which could easily lead to danger. 2. D-N and R-N require the car to be stationary: For automatic transmission cars, when shifting from D or R gear to neutral, it is best to stop the car completely before operating. This is because the gear positions of an automatic transmission are controlled by the clamping and releasing of one-way clutches. When a gear is engaged, the corresponding gear clutch is pressed under the action of the hydraulic mechanism, and when the gear is disengaged, the hydraulic mechanism releases the pressure to loosen the clutch. If the car is still moving when disengaging the gear, the wheels will continue to drive the gear mechanism, leading to increased wear on the gear clutch.

[VonAlice]

I've been driving automatic transmissions for ten years, and this question is actually quite representative. Shifting from S to D gear doesn't require pressing the brake at all, as both are forward gears and the switch won't cause any impact on the transmission. It's like switching from normal mode to sport mode while driving - you can seamlessly switch at any time. However, be aware that shifting at high speeds might cause some jerkiness, so it's better to operate below 60km/h for a smoother transition. Also, a reminder: if you're in S gear at a red light, you can directly shift to D gear without unnecessarily pressing the brake and wearing out the brake pads.

[StFernando]

Last time I drove my friend's new Camry Hybrid, I specifically tried this operation. Shifting from S mode to D mode feels as natural as switching a phone screen between landscape and portrait, with no need for brake intervention. The design principle of automatic transmissions ensures that shifting between gears in the same direction is safe. However, don’t rush to shift when going downhill—maintain engine braking. Once, while driving on a mountain road in S mode, the RPM climbed to 4000 to protect the brakes during descent. Suddenly shifting to D mode at that moment would instantly lose braking force, which is quite dangerous. For such special road conditions, it’s advisable to either stay in S mode or slow down first before shifting.

[OwenLynn]

When I first got my driver's license, I also struggled with this issue. The instructor made it very clear at the time: both D and S gears are forward gears, switching between them is like changing TV channels with a button press—no need to step on the brake. However, be careful not to switch gears frequently when starting a cold engine, as the transmission fluid temperature hasn't risen and the protection mechanism will be limited. My neighbor's car damaged its valve body this way, costing over 3,000 yuan in repairs. Nowadays, most new cars come with electronic gear levers, and the system automatically controls the shifting speed, making it smoother than in older cars.

[ReidRose]

This is a common question from car owners during repairs. In fact, the transmission control unit is quite intelligent and automatically adjusts oil pressure when shifting from S to D. However, extra caution is needed with older American models—for example, Ford's 6AT may exhibit noticeable jerks when shifting above 40km/h, where lifting the throttle works better than braking. Shifting from N to D always requires braking—it's a safety feature to prevent rolling. Modified transmission programming requires special attention, as some tuned vehicles may trigger fault codes during forced gear changes.

[Jennifer]

Having driven seven different brands of automatic transmission cars, I can tell you: switching from S mode to D mode is as simple as changing performance modes on a computer. But it depends on the specific driving conditions—suddenly shifting to D mode during hard acceleration will noticeably reduce power. Once, while overtaking on the highway, I accidentally bumped the gear lever into D mode, causing the RPM to drop instantly, which almost led to an accident. I recommend switching only after completing the overtake. Using S mode for extended periods does consume more fuel—I tested it and found it burns 1.5 liters more than D mode under the same road conditions. There’s no need to keep S mode on in urban driving unless climbing steep slopes or needing quick overtakes.