Imagine this: You're at the gas station, wincing as you pump gas into your Aardvark XZ Roadster because it's costing you $2.75 per gallon. That may seem bad enough, but what if I told you that you're voluntarily doing things to make that gas cost $3.00 or more per gallon?

It's true. Many of our bad habits on the road cost us big bucks. I read in Kiplinger's, for example, that every 5 mph you drive over 60 mph is like paying $0.20 more per gallon. Ouch. So when you're speeding along at 70 mph, you may be tacking on an extra $0.40 per gallon to your gas costs. While that may be good news for ExxonMobil (NYSE:XOM), Chevron (NYSE:CVX), and Valero (NYSE:VLO), it can quickly put a big dent in your pocketbook.

Here are a few more tips to help you save money, courtesy of the folks at

  • Driving aggressively (accelerating rapidly, braking frequently, etc.) can lower your gas mileage by 33% at highway speeds and by 5% around town. That translates to anywhere from $0.15 to $0.80 per gallon. (Driving more calmly can also save lives, as well as gas.)
  • Keep your car lighter. Driving around with just 100 extra pounds in your trunk (perhaps your cement garden-gnome collection) can reduce your mileage by up to 2%, costing you an additional $0.02 to $0.06 per gallon. Smaller vehicles are more affected by this than larger ones.
  • Don't leave your car running when you're not going anywhere. That wastes gas and gets you zero miles per gallon. The waste is greater for cars with bigger engines. Idling cars are also frequently stolen, so you may reap an extra benefit from turning yours off and taking the keys with you.
  • Using cruise control on highways can keep you from speeding, thus saving gallons and dollars (and again, perhaps lives).

If you're skeptical about any of these tips, know that they've been tested. An article at reviewed the results of such testing, finding, for example, that driving moderately instead of aggressively can save an average of 31% of your fuel. Their conclusion? "Stop driving like a maniac." Lowering your speed saved an average of 12%, while cruise control saved up to 14% (an average saving of 7%) and avoiding excessive idling saved up to 19%. Two factors that weren't too much of a factor were whether the windows or the air conditioning were used, and whether the tire pressure was correct. (Correct tire pressure yields safety benefits, though.)

Small savings can yield big bucks
For more money-saving advice, tips on great deals, and general investing guidance, I invite you to take advantage of a free trial of our Motley Fool Green Light newsletter service. There's no obligation, and I think you'll like what you see.

Longtime Fool contributor Selena Maranjian does not own shares of any companies mentioned in this article.