Hypermilers use many tactics to try to get extra fuel mileage. Some are more practical than others. Some sacrifice comfort. Some are considered unsafe by driving experts. Here's some of the techniques, and how practical and safe they are for most drivers:
Easy starts
Don't floor it. Gently accelerate to cruising speed and take it easy when you get there.
Is it worth it? Jack-rabbit starts waste gas. Gentle driving techniques are safer, too. "If you drive carefully, you can almost always meet or beat the EPA (gas mileage) estimates," says Ron Cogan, publisher of Green Car Journal.
Coast to a stop with engine off
Hypermilers call this "auto stop" for those hybrids that automatically shut off the engine in coast mode, or "forced auto stop" for switching off the key in other cars.
Is it worth it? Some hybrids are designed to do that. Coasting in neutral in other cars is generally harmless, but switching off the engine while the car is moving is downright dangerous, says Geoff Sundstrom, spokesman for the AAA. Power steering and brakes won't work and the steering wheel can lock up.
Pump up tires
Many hypermilers inflate tires to the maximum pressure listed on the tire sidewall, not as recommended on door stickers or in the vehicle's manual. Higher tire pressure can lower rolling resistance.
Is it worth it? It's potentially dangerous, says Dan Zielinski, spokesman for the Rubber Manufacturers Association, a trade group for tiremakers. Pumping up tires beyond recommendations can amount to "dangerously overinflating. This affects handling, makes tires more vulnerable to road hazards and causes tires to wear out prematurely. Stopping distance also could be impaired, he says.
Combine errands
Cars burn more gas when warming up. So hypermiler Louis Hudgin of Gilbert, Ariz., consolidates his errands to try to hit several businesses by foot from a central parking spot rather than driving to each. He tries to park so he never has to back out of a space.
Is it worth it? This makes sense if you don't mind a little exercise.
Time stop lights
Pace your driving to hit as many traffic lights on green as possible.
Is it worth it? Another great idea. More cities are trying to help by timing lights on major streets to get more cars through on green to save fuel and promote driving within the speed limit.
Drive the speed limit - or less
Cars get better gas mileage going slower on freeways because there is less wind resistance. "The higher the speed above 60 (mph), the more fuel you're losing," Cogan says.
Is it worth it? Consumer Reports tested a Toyota Camry and found it got 5 mpg more when driven at 55 mph instead of 65. California Highway Patrol Officer Heather Hoglund says slowing down is great, but stay in the right lane with other slower traffic.
Hang back from cars ahead
More space in front of your car gives you more room in which to work your speed changes in order to squeeze out more miles per gallon.
Is it worth it? More space adds more margin for emergency stops.
Don't use air conditioning
Engines work harder if they have to run air conditioning. But you also don't want to roll down the windows, which increases wind drag.
Is it worth it? You may wish you'd used some gas to keep from arriving at your destination a sweaty, wilted mess.
'Drafting' trucks
Following closely behind a truck can cut your wind resistance. Hypermilers say they don't dangerously tailgate and put safety first. Hudgin says he stays three seconds behind a vehicle in front of him to be safe. Hypermiler Wayne Gerdes says it's also possible to get drafts from trucks whooshing by in the next lane.
What the experts say: The three-second rule isn't bad, Hoglund says. But the old-fashioned rule of thumb for safety remains: Stay one car-length back for every 10 mph of speed.
AAA said some hypermilers opt to use the lowest weight of oil possible in their car's engine, hoping to reduce the friction between moving parts.
"Engineers say using too light of oil can cause major damage to a vehicle's engine," said Marshall L. Doney, AAA Automotive vice president.
AAA recommends motorists stick with manufacturer recommendations. That goes for tires, too.
The Rubber Manufacturer's Association says overinflating tires can make them more susceptible to road-hazard damage and result in premature wear to the center portion of the tread, Doney said.
"Overinflation can also cause handling issues because less tire surface is making contact with the road," he said.
The Internet has helped spread the news about how drivers can stretch their gas dollars through hypermiling.
Internet sites such as CleanMPG.com, Greenhybrid.com and several others provide ideas and hypermiler tactics.
Automakers are taking notice. Honda will install an instrument in a new hybrid it will roll out next year that cues drivers for gas-saving actions such as when to ease off the accelerator, says spokesman Sage Marie.
Many other car dealers have for years provided digital readouts that tell drivers what kind of mileage they're getting as they're driving.
Boisean Adam Winstral said while he's driving his 2006 Subaru Outback (24 mpg city/28 highway) on the interstate he tries to keep it to 65 mph.
"It's safe and saves lots of gas compared to 75 mph," Winstral said. "We get 27-28 city and 30 on the highway - loaded down."
But he said he saves the most when he "lays off the brake and gas; both cost you money."
"Jack-rabbit starts and sudden stops always use more gas," said Rick Ohnsman, a spokesman for the Idaho State Police. "There are some common sense things people should know."
He said one of the things that works and is completely legal that drivers can do is use cruise control.
"Cruise control can maintain a smoother control of the car than you can with your foot on the gas pedal," he said.
But, Ohnsman said, cruise control is designed for highway driving, where constant speeds can be maintained for long distances, not for stop-and-go traffic.
Fill your tank and record the odometer reading. The next time you fill up divide the miles you traveled by the amount of gas you bought the second time you filled up. That's your miles per gallon.
Cars with the best mpg
MakeCity/Hwy
1. Toyota Prius48/45
2. Honda Civic Hybrid40/45
3. Nissan Altima Hybrid35/33
4. Toyota Camry Hybrid33/34
5. Ford Escape Hybrid/Mercury Mariner34/30
6. Toyota Yaris29/36
7. Toyota Corolla28/37
8. Honda Fit28/34
9. Nissan Versa/Scion XD27/33
10. Hyundai Accent27/32
Source: gotmpg.com
Bob Dransfield of Meridian found he could boost his mileage from about 30 miles per gallon to more than 35 simply by driving less aggressively in his 2008 Toyota Corolla.
But that's not good enough for some drivers who call themselves "hypermilers."
Some of these drivers regularly rack up 80 to 100 miles per gallon - some in everyday cars using the same engines and tires as you. They coast with their engines off, overinflate their tires, draft behind big rigs or drive more slowly than the posted speeds.
AAA Idaho says the hypermilers' methods are questionable, even dangerous. And the Idaho State Police says some of their practices - such as driving too slowly or too closely to big trucks - are against the law.
As the price of regular gas races past $4 per gallon, you can bet more drivers will go to extreme measures to make gas last longer.
"The goals of hypermiling are positive, such as eliminating aggressive driving and saving energy," said Marshall L. Doney, AAA Automotive vice president. "Unfortunately, some motorists have taken their desire to improve fuel economy to extremes with techniques that put themselves, as well as their fellow motorists, in danger."
RADICAL DRIVING
Recent news stories of motorists getting 80 miles per gallon are inspiring - and a bit fanatical.
A recent edition of USA Today told the story of Louis Hudgin, who regularly coaxes 28 mpg more out of his 2000 Honda Insight hybrid than its federal highway mpg rating of 53 mpg.
Hudgin, who lives near Phoenix, is used to honks and offensive hand gestures when his roadmates see him driving on the white line (to reduce friction) with his air conditioning off and his windows barely cracked.
Adam Winstral of Boise doesn't consider himself a hypermiler, but he has upped his mileage by adopting some of the ideology.
"Coasting to red lights, turning the engine off at long red lights: It's simple, and you don't have to piss others off," Winstral said. "If somebody's on my tail and there's a red light ahead, I might give it a little gas to avoid the rage. However, (if) nobody's behind me, ... I'm just coasting in."
Dransfield tried his own experiment. "I (first) filled up and drove my regular way of driving. ... This worked out to 30.29 mpg," Dransfield said.
The next time he filled up, "I tried to drive extremely conservative, coasting when possible, being aware of my foot on the gas pedal. ... This worked out to 35.83 miles per gallon."
That's about 52 more miles on one tank of gas.
That's the kind of driving that experts say won't cause any problems. But cutting off your engine or putting it in neutral to coast on a roadway - or worse, rolling through stop signs - is unsafe and illegal.
Such actions put drivers at risk. Turning off an engine means no power steering or brakes and limits how they will react to quickly changing traffic conditions, the AAA's Doney said.
Rick Ohnsman, a spokesman for the Idaho State Police, said that if traffic officers see someone driving too slow or driving on the white line, there's a good chance that person will get stopped as a DUI suspect.
"Even if we learn they're not drunk, they could get a ticket for failure to maintain a lane," Ohnsman said.
And long before gas prices shot above $4 a gallon, police were stopping people for following too close. Hypermilers call it drafting; everyone else calls it tailgating.
Drafting may be OK for NASCAR drivers, but it's not worth getting pulled over for, Ohnsman said.
"It might save a little, but not nearly enough to warrant the danger," Ohnsman said. "The savings are minimal, anyway."
David Kennard: 377-6436.USA Today writer Chris Woodyard contributed to this story.
