‘Hypermilers’ court danger on the roads


ORLANDO, Fla. — As record-high fuel prices continue to stress household budgets, many motorists are looking for ways to improve their vehicle’s fuel economy — sometimes to the point of putting their lives in danger.

Some motorists have gone to extreme measures to conserve fuel while driving by ‘hypermiling’ — trying to exceed the EPA estimated fuel efficiency of a vehicle by drastically modifying driving and maintenance habits.

“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.”

Rolling stops

Examples of the dangerous hypermiling techniques include cutting off the vehicle’s engine or putting it in neutral to coast on a roadway, tailgating or drafting larger vehicles, rolling through stop signs and driving at erratic and unsafe speeds.

“These practices can put motorists in a treacherous situation where they could lose power steering and brakes or be unable to react to quickly changing traffic conditions,” Doney said.

“Not only are these extreme driving behaviors dangerous, many of them also are illegal.”

Easy does it

Doney said there are several safe and legal driving techniques motorists can implement to conserve fuel, such as smooth and easy acceleration and braking, maintaining a steady speed, using cruise control and looking ahead to anticipate changing traffic conditions.

Manufacturers know best

Hypermiling techniques are not limited to driving style. How motorists maintain their vehicles is also key in reaching optimal fuel economy, but extreme measures can be harmful to a vehicle.

Keeping tires properly inflated can improve fuel economy by 2 to 3 percent, according to the U.S. Department of Energy.

However, some drivers have taken this advice too far by over-inflating their tires, which the Rubber Manufacturers Association reports can make them more susceptible to road hazard damage and result in premature wear to the center portion of the tread.

Over-inflation can also cause handling issues due to less tire surface making contact with the road.

Using the recommended grade of motor oil is also helpful in improving fuel economy. However, some hypermilers opt to use the lowest ‘weight’ motor oil (or that with the lowest kinematic viscosity) on the market. However, motor oil is not a fluid that can be freely interchanged and using too light of oil can cause major damage to a vehicle’s engine.

In both instances, auto maintenance experts recommend motorists check their owner’s manual for the manufacturer’s recommendations.

Tires should only be inflated to the pressures specified by the vehicle manufacturer — and not what is listed on the sidewall of the tire. Motorists also should use the lowest grade motor oil recommended by the manufacturer for their climate.

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