How Does Driving a Manual Transmission Affect Gas Mileage?

As a seasoned engineer and car salesman with over 20 years of experience in both professions, I feel qualified to address the question of how driving a stick shift (manual transmission) impacts gas mileage. Throughout my career, I have observed a significant evolution in this area, particularly in the Toyota Corolla, a widely popular Japanese car.

Historical Observations

Early in my car-selling career, there was a noticeable difference in fuel efficiency between automatic and manual transmissions. For instance, in a 2003 Toyota Corolla, the advertised fuel efficiency on the window sticker was 38 mpg on the highway for the automatic vs. 41 mpg for the manual. However, as automatic transmissions have evolved, they have become more advanced, featuring more gears (5, 6, 8, 10, CVTs, and hybrid options) that have resulted in greater fuel efficiency for automatics. Today, it is common to see automatic transmissions in the 40 mpg range, whereas most manuals do not even offer manual transmission as an option anymore.

Modern Tendencies

Currently, the gap between fuel efficiency of manuals and automatics has narrowed significantly. Using the 2022 Toyota Corolla as an example, an automatic transmission might list 42/43 mpg on the window sticker, compared to 37 mpg for the manual. These figures illustrate that the advancements in automatic transmissions have made them more fuel-efficient than many manual options.

Driving Technique and Efficiency

Fuel efficiency can be dramatically improved when driving a manual transmission, especially if you know what you're doing. One of the key benefits comes from the absence of a torque converter, which can slip and waste energy. Additionally, by choosing the appropriate gear, you can maintain the engine speed in its most efficient range. By driving economically and making informed gear selections, you can achieve better fuel mileage than the car's advertised efficiency.

Conclusion

In conclusion, while the advancements in automatic transmissions have made them more fuel-efficient, driving a manual transmission can still provide significant benefits in terms of gas mileage, especially with experienced and skilled drivers who take advantage of the more manual control over the driving process.