
Normally, coasting in gear is the correct approach because the electronic throttle takes vehicle speed into account, regardless of whether it's in neutral. Coasting in gear is safer. When the speed drops and you feel it's about to lug, shifting to neutral and lightly braking is generally fine. Keeping the clutch depressed or in a semi-engaged state can damage the clutch. If the light turns green while coasting in neutral, press the clutch and shift into the appropriate gear based on your speed, trying to avoid any jerking. For example, at 20-30 mph, shift into third gear, and around 40 mph, you can shift into fourth gear.

When I was a beginner driver, I tried coasting in neutral. That is, after starting a manual transmission car, pressing the clutch pedal, slowly shifting the gear lever into neutral, and letting the car coast on its own. At this point, the engine speed drops, and the car moves forward by inertia, which sounds fuel-efficient, but it's actually not recommended. In a manual transmission, if you don't do it properly, it can easily lead to loss of control when going downhill or slower reaction times during emergency braking. It's even more dangerous with an automatic transmission—don't even attempt it, as it could damage the transmission. Now, I always drive in gear to maintain engine braking, which is safer. Additionally, checking the car's condition is crucial, such as ensuring the braking system is functioning properly, and avoid trying this in busy urban areas. Beginners should learn the basics from driving school and never take unnecessary risks by being overly clever.

As a veteran driver with over a decade of experience, I don't think coasting in neutral offers any real benefits. The operation is simple: for example, in a manual transmission car when you're driving at low speed, just press the clutch pedal all the way down and shift the gear lever to neutral, and the car will coast by inertia. But be careful not to try this on downhill slopes or curves, because without engine braking, the braking distance will increase, making accidents more likely. Coasting in neutral with an automatic transmission is even worse, as it may cause transmission overheating or oil pressure issues. I've also noticed many people think it saves fuel, but actual tests show it's completely ineffective while increasing risks. In daily driving, I simply maintain the gear while coasting, which is more stable and reliable, and also complies with traffic regulations. Experience has taught me that safe driving is far more important than minor maneuvers.

From a mechanical perspective, coasting in neutral is straightforward: after starting the vehicle, depress the clutch and shift to neutral, temporarily disengaging the engine from the drivetrain load, allowing the car to move by momentum. This is feasible in manual transmissions but must be done at low speeds on flat roads to avoid clutch wear or loss of control. However, modern electronic systems like ABS can be disrupted, reducing braking efficiency. My research on vehicles found that automatic transmissions are more prone to overheating and damage when coasting in neutral due to insufficient oil pump operation. In reality, engine braking mode is simpler, safer, and better for vehicle maintenance. Discussing more about transmission principles helps explain why this method is outdated.


