Observe the Speed Limit While each vehicle reaches its optimal fuel economy at a different speed (or range of speeds), gas mileage usually decreases rapidly at speeds above 60 mph. As a rule of thumb, you can assume that each 5 mph you drive over 60 mph is like paying an additional $0.20 per gallon for gas.

Observing the speed limit is also safer.

Remove Excess Weight

Avoid keeping unnecessary items in your vehicle, especially heavy ones. An extra 100 pounds in your vehicle could reduce your MPG by up to 2%. The reduction is based on the percentage of extra weight relative to the vehicle’s weight and affects smaller vehicles more than larger ones.

Avoid Excessive Idling

Idling gets 0 miles per gallon. Cars with larger engines typically waste more gas at idle than do cars with smaller engines.

Use Cruise ControlUsing cruise control on the highway helps you maintain a constant speed and, in most cases, will save gas.

Use Overdrive Gears When you use overdrive gearing, your car’s engine speed goes down. This saves gas and reduces engine wear.

Note: Cost savings are based on an assumed fuel price of $3.23/gallon.