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Memorial Day Memo: Don't Drive Like an Idiot (or My Brother)

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fuel economy, driving tips
I was a Mets' fan on the other side. Pennants hurt aerodynamics. (Jim Motavalli photo)It's not often that you're given total license to, well, drive like my brother. But that was the mission when Chevrolet handed me a 2011 Cruze LTZ (rated at 24 mpg city, 36 highway with the 1.4-liter EcoTec engine) and, as a reminder of how not to drive during the Memorial Day weekend, told me to waste gas any way I could. I found I was good at it.

GM did its own test with two engineers, the good one and the bad one. The good one, Ann Wenzlick, squeezed 37 mpg out of the Cruze, which would mean 575 miles per tank and gas costs of $1,621 per year. The bad one, Beth Nunning managed to do 40 percent worse: 21 mpg, 325 miles per tank and gas at a whopping $2,857 annually.

But I did Nunning one better. Driving an identical Cruze, in a 20-mile run that included local and highway driving, I got 14.8 miles per gallon. Isn't that awful? Driving it conservatively, I got up to 28.4 mpg, so I obviously have a Jekyll and Hyde personality.

To get the terrible results, GM helped me along by:
  • Loading the trunk with 250 pounds of lawn food.
  • Reducing the tire pressure by five pounds on all four corners.
  • Putting up separate Mets' and Yankees' flags on the back windows. (People must have thought I have serious commitment issues.)
  • Driving with the windows down, the AC cranked and the gas cap loose--while also ignoring the benefits of cruise control.
  • Moving slowly in the McDonald's drive-through lane. I'm not a regular, so I really noticed how much time you spend starting and stopping before you've paid and the goods are delivered.
The trunk ballast weighted 250 pounds. (Jim Motavalli photo)For the good drive, I had inflated tires, no trunk load, cruise control, and good behind-the-wheel habits. I pottered along, which is the way I always drive! I'm no speed demon under normal circumstances, even when BMW has loaned me an Ultimate Driving Machine.

So if you want to save money on the road this weekend, or any weekend, follow these simple tips. I know you've heard them before, but did those words of wisdom change your behavior?

Check tire pressure. If your rubber is 10 pounds under it can cut fuel efficiency by three percent.

Get rid of that rooftop carrier. At highway speeds, up to a third of your fuel is put to use just overcoming wind resistance. So anything you put up there, including those silly sports flags, will cut into economy.

Stop carrying junk around. The EPA says that every 100 pounds of weight can cut fuel economy by two percent, so that lawn food had a five percent penalty.

Bundle your errands. Your engine is up to 50 percent more efficient when it's warm, so if you combine your trips you're going to save fuel. Cutting out the extra loop to go back home further helps with economy.

Stop idling away money. Letting the car run while you're in Starbucks for 15 minutes uses up a quarter of a gallon of gas, or $1 at current prices.

The good things you can do include taking it easy, since driving smoothly (the opposite of what I did) improves your mileage by 20 percent, driving the speed limit (cruising at 80 instead of 70 costs you four mpg on the highway), and using cruise control. There is a great debate over whether the windows should be up or down, but the rule of thumb is to have them down with AC off at slow speeds, but up with AC on during highway drives. According to Wenzlick, the increased air pressure from driving fast with windows down "acts like a parachute to slow you down, consuming much more energy than air conditioning ever will."

Rob Verdi, who got training from Chevrolet on good driving techniques, showed me some of the tricks of the trade in this video:



Popular Mechanics adds: coast to a stop at intersections, don't accelerate to highway speeds too slowly (as bad as jackrabbit starts), and make as many right turns as possible. I know it sounds weird, but FedEx does it. And in a further round of useful tips, keeping your car maintained is a good idea, too.

OK, I'm sold, but then I'm a fuel miser in on the highway, anyway. Besides, driving like an idiot made my stomach upset.
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fuel economy, driving tips

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