Potential Consequences of Shifting Automatic Car into Gear While Moving Backward

Constantly accelerating pace and growing road traffic in cities often forces you to make hasty decisions when you are behind the wheel to reach the destination point in time, but in some cases it happens at the expense of the car’s operability. For instance, it has been widely debated on how it will affect the car equipped with the automatic transmission, if you shift your car from R to D gear while still moving backwards.

In fact, in case if your automatic car moves backwards really slow or rather crawls with the speed limited to 2-3 km/h, then you don’t have to worry much about possible negative consequences for your transmission unit. But if you decide to exceed this speed limit be ready to visit the nearest workshop for diagnostics and repair. To understand how this action of the driver affects the transmission, you have to understand the principle of operation of this complex unit.

Useful tips on driving an automatic car

Most automatics are fluid-operated units where the gearbox and the engine are linked by means of a torque converter that ATF flows through. When driving the ATF pressure will increase, thereby facilitating to precise gear shifting and smooth application of power to the wheels. These units are designed to ensure smooth and consistent feed of power to the wheels without experiencing any inconveniences.

The process of gear shifting in automatics occurs thanks to locking and unlocking the different parts of its planetary gearset. The locking of gears happens via clutches and bands facilitated by ATF. These clutches and bands are supposed to ‘slide’ a bit when engaging a gear thanks to ATF, which absorbs some of the transition, thereby ensuring smooth and safe gear shifting.

In practice, the situation discussed in this article may occur when you have to stop your car at a traffic light on hilly or elevating roads. When you release the brake pedal, the car will begin to slowly go backwards before power is transferred through ATF to force your car moving forward. The low speed in this case means shifting into D gear when moving backward is unlikely to cause any serious damage to the transmission mechanism.

Check out what happens if you put your automatic car in REVERSE while driving

But in case when your car reverses at higher speeds (5 km/h and higher), then it will be reasonable to bring your car to a full stop before engaging D gear. The same recommendation applies when it pops into your mind to engage R gear while traveling forward. Otherwise, you run the risk of seriously damaging one of the most expensive components in your car.