Is Shifting an Automatic Transmission to Neutral While in Motion Damaging?
Many drivers wonder if shifting an automatic transmission to Neutral while in motion can harm their vehicle. This practice, while occasionally necessary under specific circumstances, carries certain risks and potential damages. Let's explore the implications in detail.
Risks of Shifting to Neutral While in Motion
The act of shifting to Neutral while the vehicle is in motion can lead to several issues, primarily concerning control, transmission wear, and fluid circulation.
Loss of Control
One of the most significant risks of shifting to Neutral while driving is the loss of control over the vehicle. Unlike manual transmissions, automatic transmissions are dependent on engine braking for maintaining control, especially on downhill slopes. When in Neutral, the engine's power is no longer connected to the wheels, leaving the driver with no engine braking to aid in controlling the vehicle's speed.
Transmission Wear
Frequent shifts in and out of Neutral, particularly at high speeds or under load, can place unnecessary stress on the transmission components. This repetitive action can lead to premature wear and tear on gears, bearings, and other critical parts of the transmission, shortening its lifespan.
Fluid Circulation
Another important factor is the transmission's fluid circulation. When in motion and in Neutral, the transmission pump may not be as effective at circulating the fluid, which is crucial for proper lubrication and cooling. This can result in inadequate cooling and lubrication, leading to potential transmission damage over time.
Potential for Damage
Certain automatic transmissions are designed with safety features to prevent shifting into Neutral while the vehicle is moving. Forcing the shift could potentially damage the shift linkage or other components, leading to costly repairs.
Safe and Proper Usage of Neutral
While shifting to Neutral while in motion can be unsafe, there are occasions where it is necessary and safe. For example, when a vehicle is being towed, the transmission needs to be in Neutral. Additionally, drivers can shift to N mode just before coming to a stop at an intersection or red light, and then engage the parking brake.
Another important point is the cultural design feature in North American automatic transmissions. When the vehicle's gear is in Drive and you attempt to shift to Neutral, the safety feature prevents the selector from engaging Reverse. To demonstrate, try shifting while the car is stationary; the selector will only go into Neutral, not Reverse, even if you push the lever with force.
No Harm from Coasting or Braking in Neutral
Coasting or braking in Neutral is generally safe and can even reduce the wear on the transmission. Shifting to Neutral before braking can help reduce the wear caused by continuous downshifting, which helps in maintaining transmission health.
In summary, while shifting an automatic transmission to Neutral while in motion can lead to risks such as loss of control, transmission wear, and fluid circulation issues, the practice is not always harmful. Understanding the proper usage of Neutral and respecting the vehicle's design can help ensure safe and efficient driving.