We learn at a young age that what goes up must come down, which may explain why we feel such shock and awe at the gas station these days. Up, up, up and so far just a hint of down.

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Keep tires inflated, among other things, to save money on gas. — SuperStock/Getty Images

If you want to write an angry letter, send it to Moammar Gaddafi. He’s the one who helped set off a rise in global oil prices months ago — faced with a rebellion against his years of dictatorship, he launched armed attacks that disrupted oil fields and tanker ports on the Mediterranean.

This year, gas breached $4 a gallon nationwide — and just as the economy is trying to dust itself off and stagger to its feet.

Short of applying for a job at OPEC, there isn’t anything you can do to lower the cost of gas, but we can all stretch our fuel dollars. So we sought out some experts to give us a rundown on the best ways to save at the pump.

• Lose weight. Not you — the car. Bob Toth, director of new products and innovation for Goodyear, suggests emptying the trunk of excess junk or removing a luggage or bicycle rack that usually goes unused. “You can save 1 to 2 percent of your fuel by getting rid of an extra 100 pounds,” Toth says.


• Keep your speed down. Most vehicles “have their best efficiency at 40 to 50 miles an hour,” says Roger Clark, a fuel economy engineer at General Motors. “Every 10 miles an hour above those speeds, you lose four miles a gallon.” So if you can take a rural road with few or no traffic lights, your gas tank is better off than being on a high-speed freeway.
  
  
• Do all your errands in one trip. You’ll save if you group them together rather than doing one in the morning and another in the evening. It takes a lot of gas to start a cold engine and get it running at peak efficiency. Which isn’t to say you need to sprint into a store and out lest your engine lose its heat. You can do a leisurely shop. “It takes a couple hours for your engine to cool down,” Clark says.
  
  
• Avoid idling. In 2009, Phil Reed, the senior consumer advice editor at the car guide Edmunds.com, found in tests that drivers who cut idling to no more than one minute can typically make their gas last 19 percent longer. “Looking for ways to reduce excessive idling is an untapped area of fuel savings, whether it’s people crawling through crowded drive-up windows or parents waiting to pick up their kids from school,” Reed says. “If you are parked safely, shut it down — and save money.”
  

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