What Does D3 Mean In A Car? Understanding Your Gears On Automatic Transition

Last Updated on February 9, 2023 by Leepu Da Maxim

Cars with automatic transmissions have different gears that you can choose from, including P, R, N, D, S, L, and D3. The D3 Gear means drive three and is used to lock the third Gear to not shift to other higher driving gears. This Gear comes in handy to keep you safe when driving on roads where you need to keep your speed constant.

Key Takeaways

  • If your vehicle has automatic transmission then you will see the D3 and it is a gear position
  • “D3” is a lower-gear position and it is usually used in highway driving and moderate acceleration
  • Driving in the D3 gear will allow the brake pads from overheating which is very important for highway driving
  • Driving in the D3 gear will provide a good balance of acceleration and fuel efficiency

What Are The Advantages Of Driving In D3 Gear?

What Are The Advantages Of Driving In D3 Gear

The D3 Gear has several advantages when used. This Gear uses the first three gears of your vehicle’s automatic transmission and locks the third Gear as the highest. There are several unique advantages of using this Gear for different driving situations. Let’s look at some of the main benefits of driving in D3 Gear.

1. Guarantees Safer Driving

When you engage D3 Gear, you have more control over the vehicle, especially if the car is prone to slipping. D3 lets you run at lower gears to give you more traction because the wheels won’t spin that fast. You are most likely to notice the increased level of control when driving in rainy weather with this Gear engaged. The engine braking function also adds extra safety by limiting the speed when you are going on steep slopes.

2. It Helps To Minimize Brake Wear

When driving in D3, the engine’s speed will automatically regulate, meaning you won’t need to use the brake pedal as much. If you engage the D3 Gear when driving downhill, you won’t wear out your brakes, and you can stay for long without needing to replace them.

3. Offers Quick Throttle Response

When you are driving in areas where you will rely more on throttle responses than speed, the D3 Gear will come in handy. The lower gears will help get the RPM up higher for faster acceleration when driving in the city and pulling out of heavy traffic. This Gear is essential in such situations, but you need to ensure you don’t drive it long distances to extend the motor’s longevity.

When Should I Use The D3 Gear?

The D3 Gear not only gives you a versatile driving experience but also comes in handy when driving in various conditions to ensure you are safer. One such scenario where D3 adds to your safety is going downhill.  When driving downhill, this Gear helps to achieve engine braking to keep your powertrain safe and keep you from running at high speeds downhill. The Gear restricts the airflow that causes a high manifold vacuum causing deceleration on your car.

You can also engage the D3 Gear when driving uphill to keep your car from slipping. This works because this Gear will keep the transmission at the third Gear or the same Gear to keep the vehicle from losing traction. The D3 Gear is most convenient when the road is not too steep. 

When you are hauling a load or towing another vehicle, you can engage the D3 Gear to help you keep your speed in check. You can also use it when driving in the rain to control the speed and avoid keeping your foot on the brake pedal.

You can use the D3 Gear on roads where you need to pick up a little speed, such as city and highway driving. It is recommended to use this Gear with speed limits of 60 km/h and below since you are restricted to the first three gears.

How To Use D3 Gear In Automatic Cars

1. Start your car using the drive (D) mode first. This will engage the lowest possible Gear and provide a high torque which comes in handy when moving slowly.

2. Drive on D mode as you accelerate so that your speed gets to 40-60 km/h before you shift to D3.

3. Once you’ve attained the desired speed, press the button on your gear selector and put the Gear on D3. This button is usually installed to ensure you don’t engage a gear that might cause accidents.

4. If you need to slow down to speeds below 30km/h, engage the D mode and make sure to accelerate before engaging D3 again.

Other Automatic Transmission Gears And What They Are Used For

Mechanical transmission gears have different drive modes that may not be obvious, especially for first-timers. These modes are used in various driving situations and road types. Let’s look at them in detail to help you understand what they are used for.

L (low)

This Gear, when engaged, ensures that your engine stays in the lowest possible gear ratio or the first Gear. In older models, this mode locks the 1st Gear, while in newer models, it allows the Gear to shift to the next when the revolutions per minute increase to prevent any damage to your car’s transmission and engine. This Gear is mainly used to keep a consistent low speed. For example, when on moving traffic in a steep hill or winding road to give you enough climbing power.


The two-mode allows your car to use only the first two gears of your vehicle and maximize each Gear’s RPM. This mode locks in the 2nd Gear in newer models but can move up to the next Gear when you reach high RPM to prevent engine damage. You can use this Gear in pretty steep climbs where speeding up a little doesn’t threaten your safety.

Frequently Asked Questions On D3 And Other Gears On Automatic Cars

Q. At What Speed Should I Use D3 Mode?

D3 is ideal for use with speeds between 40-60 km/h in the city or on highways. D3 is recommended when driving in a busy town to enable your car to respond well while driving at lower speeds. The D3 mode only engages the first three gears for low speeds.

Q. Is D3 Used At Low Speed?

Yes, the D3 mode is ideal for low-speed driving because it engages the first three gears. This Gear helps the car achieve optimum performance and may disengage when the highest RPM is reached. When driving in hilly or steep locations, driving on D3 is highly recommended.

Q. What Is S Mode In An Automatic Transmission?

S mode is mainly found in sport utility vehicles, and it means Sport mode. This mode is used to enhance shifting and throttle response.

Q. Why Doesn’t My Car Come With A D3 Mode?

Some manufacturers do not include D3 mode on their automatic transmission. This mode is often replaced by the S mode, which serves the same purpose.

Final Word

Understanding every aspect of your car is every car owner’s dream. When you know what each gear mode or function is, you are better placed to enjoy the most out of your car. Using the D3 Gear in your vehicle will help you have your brake pads longer and your engine functioning excellently. We hope that this post has enlightened you, and you are now eager to try out the different transmission gears and see how you like them.