If you were paying attention in your high school physics class, you know that engine size and acceleration are only partially responsible for how fast you go and how fast you burn through a gallon of gas. Fuel economy also depends on things like weight, wind resistance, friction and driving habits.
As part of President Obama’s plan to decrease America’s dependence on foreign oil and lessen the environmental impact of gas pollution, all new cars and light trucks will have to average 54.5 mpg by 2025. By improving one or more of the components that determine fuel efficiency, car manufacturers can achieve that goal. As a driver, you can also do your part when you get behind the wheel of your vehicle.
Fuel Economy Tips: How You Can Improve Your Gas Mileage
Aggressive driving can result in a five percent decrease in gas mileage in city driving and as much as a 33 percent decrease at highway speeds, according to the U.S. Department of Energy. Rapid acceleration, speeding and hard braking makes your engine work harder and need more fuel.
Carrying too much weight in your vehicle is also robbing you of better mileage. While you don’t want to throw Grandma out the back seat, avoid hauling all that junk in your trunk. While putting 500 pounds in the back of your Dodge Ram pickup truck won’t have much impact, if you put that same 500 pounds in a Honda Civic, it will.
Other things that you can do to gain better mileage are to make sure your tires are properly inflated, turn off your engine instead of letting it idle for 10 minutes and keep your car tuned-up.
Wind Drag and Aerodynamics
Auto manufacturers and engineers use wind tunnels to test the aerodynamics of a new or redesigned car. By shaping parts of the body of the car, changing the grill or making the car lower to the ground, they can reduce the drag on the vehicle. If you have ever stuck your arm out of the window of a car traveling at 70 mph, that powerful force that pushes against you, is the same force that your car must overcome. Turn your hand sideways and it becomes more aerodynamic, like an airplane wing, and you will need less strength and energy to keep your hand and arm in place.
When the 2009 Ford Flex hit the showroom floor, it had a coefficient of drag of just 0.355, significantly better than its Asian competitors. According to the Flex team, the wide, low stance of the vehicle reduced wind resistance by forcing more air over the vehicle and not under it, where it could create the most drag.
The vehicle’s driveline also contributes to its fuel efficiency, TireBuyer adds. That includes your drive shaft, transmission and axles, which receive the power to turn the wheels and propel your vehicle. Using lighter materials like aluminum instead of steel and manufacturing the driveline parts to precise specifications can reduce friction and add a few miles of travel distance to each tankful of gas. Unfortunately, to do this, you’d need to take your vehicle to a body shop, and changes to these areas could result in voiding warrantees.
No matter what model vehicle you own, if you understand some basic concepts of physics, you can make your car more efficient. Good habits like keeping enough air in your tires, accelerating slowly and not keeping your set of 50 pound dumbbells in your trunk will help give you better gas mileage. Friction, drag and inertia can all rob you of fuel efficiency. A car manufacturer can make a more aerodynamic vehicle, but can not control the way you drive it. Be smart about the way you drive and you will use less gas, save money and also do something good for the environment.