Slowing Down and Driving Defensively

• Hypermilers have developed a wide range of techniques to maximize fuel efficiency, and some may seem like too much trouble to the average driver. The community's most important insight may also be the easiest to understand and apply, however: slow down and relax. Cars burn more fuel at higher speeds, so driving at or below posted speed limits will reduce pain at the pump. Aggressive drivers who start suddenly and weave in traffic will consume more gas than those who go with the flow of traffic and accelerate slowly and steadily.
  
  

Using Cruise Control on the Highway

• Cruise control can help lead-foot drivers cut their fuel consumption, particularly on highways where traffic flows smoothly at a constant speed. As one writer explained on CNN.com, "using cruise control cuts down on unnecessary speed changes which can eat up gas and it prevents 'speed creep,' the tendency for a driver's average speed to increase with time spent on the road." Some hypermilers warn that cruise control still wastes gas on hills, and recommend using it only on flat roads.
  
  

Reducing Weight and Drag

• The heavier the vehicle, the more energy it takes to get it moving. Drivers can improve fuel efficiency by taking out unnecessary cargo or unused removable seats. Aerodynamic drag also affects gas consumption, and certain car features and driver behaviors can increase drag. Driving with open windows or sunroofs burns gas faster, and roof racks also break up the aerodynamic lines of most cars. Drivers who do not use their roof racks should consider removing them to reduce drag.
  
  

Keeping Up with Maintenance

• A properly maintained car will perform better than a neglected one under any conditions, but some maintenance tasks have an outsized effect on fuel economy. Underinflated tires make a car's engine work harder, so drivers should check tire pressures regularly. The U.S. Department of Energy has found fuel economy benefits from engine tuning, replacing worn-out air filters and other parts, and using motor oils designed for particular vehicles.
  
  

Techniques to Avoid

• Drivers can conserve fuel by closely following a larger vehicle such as a tractor-trailer, a technique hypermilers call "drafting" and everyone else just calls tailgating. The risks of collision do not justify a marginal improvement in fuel efficiency.
  
  Some hypermilers overinflate their tires past manufacturer specifications. This dramatically cuts tire drag, so the wheels will roll without a foot on the gas. Unfortunately, overinflation also reduces the amount of tire surface in direct contact with the road, increasing stopping distances.
  
  Drivers can also trim fuel consumption by using the Forced Auto Stop method (FAS), but this can carry significant risks. The driver saves gas by coasting with the engine turned off, but modern power steering and brakes may not work properly. In an emergency situation, a driver using FAS might not have enough time to restart the car to avoid an accident.