Why does the car shake violently when holding the brake in D gear?

[VonCalvin]

When the car is held in D gear with the brake pressed, the transmission fluid inside the torque converter flows at high speed and is subjected to significant shear forces. If this state persists for too long, the temperature of the transmission fluid will rise. The engine, due to increased load, will inject more fuel, leading to higher fuel consumption and an increase in engine temperature. This can cause the car to shake easily. Prolonged use of D gear while holding the brake is detrimental to both the engine and the transmission. Check the quality of the transmission fluid: For automatic transmission vehicles, it is essential to regularly inspect the quantity and quality of the automatic transmission fluid. Typically, an automatic transmission service should be performed every 20,000 to 30,000 kilometers, including the replacement of specialized automatic transmission fluid (ATF). Monitor dashboard information: Develop a good habit of constantly monitoring dashboard information. While driving, always observe the dashboard for any warning lights. If the transmission fault light flashes, the computer indicates a transmission issue, which may manifest as difficulty starting, failure to shift gears, or inability to reach high speeds. In such cases, avoid long-distance driving and immediately contact a professional automatic transmission repair center for fault diagnosis. Regularly clean blockages: Ventilation and cooling are crucial. Periodically clean surface blockages on external components like the radiator and cooling fins to ensure better ventilation and cooling, thereby preventing high temperatures from damaging internal transmission components.

[Corinne]

I've encountered a similar situation with my decade-old car. When in D gear and stepping on the brake, the car body shakes violently, feeling like the entire cabin is vibrating. The main cause is likely unstable engine idle speed. Issues like worn spark plugs, faulty ignition coils, or incorrect air-fuel ratio can all exacerbate engine vibration at low RPM. For automatic transmission vehicles, the torque converter connects the engine and transmission in D gear. When you brake hard, it forcibly locks up - if there's internal wear or slippage, this can easily cause shaking. Another possibility is aged or damaged engine mounts. Those rubber pads are designed to absorb vibrations, and when they fail, the shaking gets transmitted to the car body. I suggest first trying to shift to N (neutral) gear and see if the shaking persists when braking. If the shaking reduces, the problem is mostly with the engine; if it remains severe, it's probably transmission-related. Get it checked by a professional shop immediately - don't delay until it becomes a major repair that could compromise driving safety.

[Trevor]

My car has been doing the same thing recently. When I stop at a red light in D gear and press the brake, the car body suddenly shakes a few times, which makes me feel really nervous. The most common causes include abnormal engine combustion, such as clogged fuel injectors leading to uneven fuel-air mixture, or a dirty air filter restricting air intake. For the automatic transmission, if the torque converter has unstable internal oil pressure or blade slippage, it can cause severe vibrations when the brake is pressed. Another potential issue is a leak in the brake system's vacuum booster, which affects overall balance. This is a significant hazard—if you suddenly lose control, it could be disastrous. So, I recommend checking the dashboard immediately for any warning lights and then testing the car's condition in P and N gears. If everything confirms an abnormality, take it to a repair shop for a comprehensive diagnosis as soon as possible—don’t skimp on this expense. Safety should always come first; don’t let the shaking disrupt your daily commute.

[AdamFitz]

Severe body shaking when stepping on the brake in D gear usually stems from the engine or transmission. From my own experience: First check if the idle speed is stable - instability may indicate spark plug failure or intake system issues; If it only occurs in D gear, there's a high probability it's caused by torque converter slippage in the automatic transmission. The inspection is simple: start the engine to listen for abnormal sounds, then try shifting to N gear to compare vibration changes. Timely maintenance can prevent this, such as regular transmission fluid changes and throttle body cleaning.

[AsherLee]

My car had this issue too. When stopping in D gear with the brakes pressed, the shaking was terrifying, which is usually related to the transmission or engine. The torque converter connects power in D gear, and pressing the brakes actually increases the load. If it's aged, damaged, or there's too little transmission fluid, it can cause shaking. Engine-side reasons like loose engine mounts or ignition system failures shouldn't be ignored either. Temporary solution: Shift to N gear when stopping at lights to reduce vibration. Long-term solution requires maintenance, such as changing the transmission fluid every 2 years and checking engine mounts. Don't underestimate it; fixing it early saves trouble.