A manual transmission is more efficient than an automatic transmission. It contains far less working components and is 15% more efficient at transferring power to the wheels than an automatic transmission. This results in less energy spent to propel the vehicle down the road for a given rpm and less fuel consumed. Manual transmissions produce much less internal friction than
1. Driving Tips
The best way to save gas mileage with a manual transmission is to shift into the next higher gear as early as possible when driving. This keeps the engine at a low rpm all the time. As you may know the higher the rpm while driving the more gas you will waste because the motor is pulling more air/fuel mixture into the cylinders per unit time. Make sure to use 6th gear on the highway if your vehicle is so equipped. You can easily save 10-15% in gas mileage by following these low rpm driving techniques.
2. Buying Advice
When purchasing a new vehicle and fuel economy is of utmost importance follow these tips regarding transmission purchase. If possible buy a manual transmission with the highest number of gears possible. Most manual vehicles have 5 gears, some 6. If buying a manual is out of the question, make sure you choose an automatic with more than 4 gears. One of the reasons older vehicles suffered in fuel economy compared to newer models is because they all had 4 gear automatic transmissions (many vehicles in the 60’s and 70’s had only 3 gears!). Automatics today come with 5,6, or even 7 gears. These larger gears can greatly improve fuel economy on the highway at cruising speeds.
At MPG Enhance we have tested vehicles with and without manual transmissions. Manual transmissions are certainly more efficient and the difference between shifting quickly into the next higher gear while driving in a manual versus staying in a lower gear can make a huge difference in fuel economy. We have seen differences by just changing our driving styles of 1–5 mpg. Remember in both cases (automatic and manual) use a quality synthetic transmission fluid to further increase fuel mileage. See our transmission fluid section for more info.