Most people are basically astounded at how much a gallon of gasoline costs these days. The days of 99-cent unleaded suddenly seem as long ago as those of drive-in movies.

With gas prices higher than ever, fuel economy has become a very hot topic, and everyone is looking for a way to squeeze the most miles out of every fill-up.

Following are a few tips to help squeeze more miles out of every gallon of gas.

Tip: Use the fuel recommended in the vehicle's owner's manual. Some people think upgrading to mid-grade or premium is better for a vehicle. A quick check of the manual will tell the type of gasoline that's right for each car. Some require higher-octane gas, but for many cars, regular unleaded is just fine.

Tip: Check tires. Properly inflated tires are important for safe driving, but they're also a big part of efficient driving. Under-inflated tires need more energy to roll, which wastes fuel and makes tires wear faster. Having a good tirepressure gauge makes it easy to be safe and improve fuel economy and tire wear

Tip: Use the correct grade of motor oil. The owner's manual will tell which type is best for each car. Also, remember to look for oil labeled "Energy Conserving" on the API performance symbol.

Tip: Replace dirty air filters. A clogged air filter can reduce gas mileage, so make sure it's checked during the next oil change. A new filter will save fuel and keep impurities from damaging an engine.

Tip: Engine maintenance is essential. If the engine is poorly maintained, gas mileage will drop dramatically.

Follow the recommended maintenance schedule in the owner's manual and have the vehicle checked out if there are any unusual sounds, smells or vibrations.

Tip: Lighten the load. Extra weight requires extra fuel, so if there's anything in the trunk or cargo area that's not needed, take it out and store it elsewhere.

Tip: Be efficient with a warm engine. A cold engine (one that hasn't been started for many hours) is less fuel-efficient than a warm one. An engine warms up faster while driving than while sitting and warming up, so don't let the vehicle sit at idle for more than 30 seconds. Start it up, drive it, then shut it off between errands to conserve fuel.

Also, try to combine as many errands as possible into one trip.

Tip: Don't run the air-conditioning unless its really needed. Using the air-conditioner robs power from the engine and uses additional fuel. On cooler spring and fall days, open the windows and experiment with the vent and fan settings during short trips.

At highway speeds, however, an open window adds drag and harms fuel economy. If on the highway on a hot afternoon, use the air-conditioning.

Tip: Reduce aerodynamic drag. Unused ski racks, bike racks and cartop carriers create added wind resistance, which makes the vehicle's engine work harder. If they are not being used, remove them.

Tip: Watch speed. A vehicle's fuel efficiency decreases rapidly at speeds above 60 mph. Once a vehicle is up to speed, maintain a steady pace in top gear and use cruise control. Keeping the vehicle at a steady speed is a great way to stay safe and save gas.

Tip: Use overdrive gears on the highway. Overdrive gears reduce engine speed, saving fuel and reducing engine wear.

Tip: Relax. Aggressive driving -- speeding, rapid acceleration, hard braking -- are sure ways to reduce gas mileage. Driving smoothly and steadily saves fuel and also extends the life of the engine, transmission, brakes and tires.

Tip: Shop around. Most gas stations carry the same quality fuel, so as long as one is already on the road, keep an eye out for the lowest price. Also check online for sites that monitor gas prices in each area.