What is the most fuel-efficient speed for highway driving?

[James]

Typically, it's between 90—110 km/h. Fuel consumption increases when driving below or above this speed range. Here are some good habits for saving fuel: 1. Turn off the engine directly for longer stops: On the road, you often encounter waiting times at traffic lights. If the stop lasts more than 30 seconds, it's best to shift into park and turn off the engine. Idling for more than 10 seconds consumes more fuel than turning off and restarting the engine. 2. Filling up the tank is more economical than frequent small refuels: After each refuel, always check to ensure the fuel cap is tightly secured. 3. Anticipate distances while driving: The key to using engine braking lies in the driver's anticipation of traffic conditions ahead, timely releasing the throttle to utilize the engine's resistance for smooth deceleration. After passing obstacles, promptly accelerate to continue driving, thereby avoiding frequent brake use, which reduces speed excessively and increases fuel consumption. Additionally, this method not only saves fuel but also reduces wear on the vehicle's brake pads. 4. Perform regular checks: It's also advisable to pay attention to regular vehicle maintenance, especially the tire system and air filter, which are crucial for saving fuel. At the same time, over-inflated tires can also lead to increased fuel consumption.

[VonRafael]

I've been commuting on the highway and found that maintaining a speed between 80 to 90 km/h is the most fuel-efficient for my sedan. At this cruising speed, the air resistance is low, and the engine runs smoothly with minimal fuel consumption. Going significantly faster, like over 100 km/h, dramatically increases air resistance and fuel usage. Conversely, driving too slow, such as at 60 km/h, isn't ideal either because the engine doesn't operate at its most efficient RPM. I recommend using the cruise control feature to maintain a steady speed, avoiding sudden acceleration or braking, and ensuring the tires are properly inflated to maximize fuel savings. Over time, this can save a considerable amount on monthly fuel costs and reduce vehicle wear. Additionally, safe highway driving habits are crucial—maintain a proper following distance and avoid rushing.

[Summer]

As an ordinary driver, I've tried multiple high-speed road trips and found that the most economical speed range is between 80 to 90 kilometers per hour, as this is when wind resistance and fuel consumption reach a balance point. Exceeding 100 kilometers significantly increases wind resistance and causes fuel consumption to soar, especially on mountain roads or in windy conditions. I prefer maintaining a constant speed and using the air conditioning less to reduce load, which allows a full tank of gas to last longer. Saving fuel not only cuts costs but is also environmentally friendly by reducing emissions. It's worth mentioning that there might be differences between new and old cars, and SUVs and sedans also vary, so adjustments should be made based on your specific vehicle model. Regular maintenance, such as keeping the air filter clean and ensuring the engine runs efficiently, can also help save fuel.

[AvaLynn]

I've driven long-distance coaches and found that the most fuel-efficient speed on highways is between 70 to 85 km/h, with wind resistance being the key factor. Fuel consumption increases exponentially with higher speeds. I always use cruise control to maintain steady driving. It saves fuel and money while enhancing safety and extending vehicle component lifespan. When driving, avoid frequent lane changes and maintain constant speed. Also, check tire pressure regularly, as both overinflation and underinflation affect fuel consumption.