Save gas: Learn from 'hypermilers'

It pays to double-check your mileage, whether you have a gauge or not. "Some gauges run high," Flory says. Try this:

• Fill up your tank to the first click at the pump (don't overfuel).

• Set your trip odometer.

• Drive an exact number of miles, such as 100.

• Now refill the tank, again only to the first click, and note the exact amount of gas you just added. Let's say it was 5 gallons.

• Divide 100 by 5 to get your mileage per gallon -- 20 mpg in this case.

2 things you can do to your car

Excess weight can use up extra gas, so if you don't need that back seat, the picnic basket, the table tennis set or the 10 bags of clothes waiting to go to the Salvation Army, ditch them before you drive.

Hypermilers also avoid driving with a roof rack or pod unless it's absolutely necessary.

Though we did remove the back seat of the van, I'll tell you right now, it will be six years before we get around to removing the roof rack, which is a small one anyway, so who cares.

And you should check your tire pressure. Although some hypermilers swear by this one, Consumer Reports' Fisher is skeptical about the benefits of inflating tires to a higher pressure than a car manufacturer recommends. Hypermilers go by the maximum allowed by tire makers, numbers that are usually embossed on the sidewalls.

"Inflating tires to maximum pressure will save you a couple of miles per gallon, but it doesn't make your car handle like it should," Fisher says.

For efficiency, Flory says, make sure your tires are fully inflated, at least to the pressure specified by the automaker on the door sticker. "Most people are driving around on underinflated tires."

Flory was right. Our tires were below the 35 pounds per square inch recommended by Dodge.

A driving technique that pays off

Flory describes hypermiling as a toolbox of different strategies drivers can use, depending on their car, driving style, commuting issues, etc. You need use only what works for you, he emphasizes.

During my hypermiling lesson, Flory had me drive around an empty parking lot to get the hang of various moves. This was a good idea, not only because hypermiling requires unusual focus on the terrain, traffic and overall environment but because it's hard not to glance at the darned mileage gauge every two seconds. A smash into someone's rear bumper could be an expensive end to your hypermiling adventures.

Studies have shown that driving a steady 55 mph on the highway leads to better gas mileage, but hypermilers advocate a more nuanced strategy, situation permitting.

Let your car use the momentum of the road rather than rely on the accelerator. The following can also be used in highway driving, but exercise caution:

• Coast whenever possible. Take your foot off the gas or put the car into neutral when going downhill, pulling out of a driveway or a parking space, or when slowing toward a stop sign or traffic light.

• Accelerate to climb a hill, but (if there is no one behind you) take your foot off the gas as you crest the hill and then coast down.

• Traffic permitting, accelerate to 55 mph, for example, then switch to neutral as the car slows to 45 mph. Then speed up again. This is called pulse-and-glide.

Pulse-and-glide was easy enough to do in the rural area where we live because there's little traffic. But the technique that made a noticeable difference in our mileage was following the natural peaks and valleys of the road and coasting whenever possible.

When I took my foot off the accelerator as I eased down a slope, my gas mileage would be about 60 to 70 mpg, as opposed to about 10 mpg going uphill. When I shifted to neutral going downhill, the mileage gauge hit about 80 mpg! Intoxicating!

Committing for the long haul

I was secretly hoping my fuel costs would evaporate overnight, if not sooner.

That hasn't happened yet. Our best daily mileage while driving locally was about 22.3 mpg (those hills!). But our highway driving saw a distinct improvement, to about 35 mpg, about a 30% increase.

Even that 10% improvement in our around-town mileage means pretty big savings. We drive about 20,000 miles a year, and at 20 mpg we burn about 1,000 gallons of gas. That 10% improvement in mileage means we'll use 91 fewer gallons of $4.15 gas. That's $378 a year!

But I think we'll do even better. We have been driving with this new fuel-efficient mind-set for only two weeks, and I suspect, as with most things in life, you have to hang in there for a while before you see real changes.

I'll keep you posted on the Women in Red message board. Let me know how you're driving these days.

Published Aug. 6, 2008

< previous |  1 | 2 |