Can an AT Transmission Coast in Neutral Gear?
3 Answers
An AT transmission should not coast in neutral gear. The functions of a transmission are: 1. To change the transmission ratio, as different driving conditions require different traction forces; 2. To enable the vehicle to move in reverse; 3. To interrupt power transmission, allowing the engine to start and idle, the vehicle to shift gears or park, and cutting off power to the drive wheels; 4. To achieve neutral gear, stopping power output when the clutch is engaged. An automatic transmission is a device that can automatically shift gears based on the vehicle's speed and engine RPM, as opposed to a manual transmission. Currently, there are four common types of automatic transmissions for vehicles: hydraulic automatic transmission (AT), continuously variable transmission (CVT), automated manual transmission (AMT), and dual-clutch transmission.
As a car enthusiast, I've researched this issue myself. Technically, an AT transmission can coast in neutral (N) gear, but it's better not to do so. The main reason is that the transmission relies on lubricant circulation for cooling and protecting internal components. In N gear, the engine speed decreases, leading to insufficient lubricant flow, which can easily cause overheating and wear on gears and bearings. Especially when going downhill, losing engine braking significantly increases brake burden, creating danger if brakes fail. Modern models may have safety designs, but frequent coasting will shorten transmission lifespan. I recommend staying in drive (D) gear when descending hills - using engine braking is safer and more worry-free while protecting vehicle components. N gear should only be used for parking or towing; otherwise, repair costs can be substantial.
I've been driving for over 30 years and encountered many similar issues. Coasting in neutral (N) with an AT vehicle isn't a wise choice. When I was younger, I tried it a few times thinking it could save fuel, but the transmission started making strange noises. The mechanic said internal components had severe wear. During coasting, lubrication can't keep up, causing gears to rotate dry, generating heat and accelerating aging. More importantly, without engine braking, stopping distance increases, affecting control and reaction time. Safe driving is paramount, so I always avoid shifting to N, only using it when stopped at red lights or during car wash towing. Remember, vehicle reliability is far more important than saving a bit of fuel – always stay alert when driving.
