How to stretch your gas dollars

Candyce H. Stapen | USA TODAY

Making the most of your gas dollars is an important part of any holiday travel strategy. Even at a national average of about $3.25 per gallon, the lowest price for this time of year since 2010, fuel costs add up. By following the expert tips below on how to prep your vehicle, drive efficiently and plan your getaway, you can boost your vehicle's fuel efficiency by as much as 40% and also decrease your costs at the pump by 20 cents or more per gallon.

Prep your vehicle

Maintain correct tire pressure. Keeping tires properly inflated improves gas mileage by up to 3.3% according to the U.S. Department of Energy (DOE), which estimates that only 17% of cars have all four tires at the proper pressure. A DOE survey discovered that 85% of drivers don't know how to correctly check tire pressure.

The number posted on the tire's sidewall signifies the tire's maximum pressure and not your vehicle's optimal pressure. Your vehicle's recommended psi (pounds per square inch) is posted on the car's door jamb or in the glove compartment and listed in the owner's manual.

Be aware that cooler weather causes tire pressure to drop. "For every 10 degrees Fahrenheit that temperature drops, a tire loses one to two psi in pressure because air contracts as it cools," says Henry Kopacz, Hankook Tire Company's tire expert. Kopacz recommends that owner's check tire pressure at least once a month, preferably in the morning before driving when the tires are cool.

Pack light. "Take the junk out of the trunk," says Nancy White, AAA spokesperson. Remove the golf clubs, gardening tools, portable grills and anything else you don't need for the trip. An extra 100 pounds in your car can reduce the miles-per-gallon by up to 2%, according to the DOE.

Avoid using the roof rack. Aerodynamically, a loaded roof rack adds drag, decreasing fuel economy by as much as 5% notes DOE. Try to pack needed items in the trunk or in the car's interior.

Drive efficiently

Do not speed. Racing down the road decreases both safety and fuel economy. For every five mph over 50 mph that you gain in speed, you lose fuel efficiency notes the DOE. Cruising at 55 mph is the equivalent of paying 25 cents more per gallon and zooming along at 65 mph is like adding 75 cents to the cost of each gallon of gas.

Monitor your driving style. Easy does it makes for maximum fuel mileage. Rapid acceleration and quick stops as well as speeding can lower gas mileage by 33% on the highway and 5% around town according to the DOE. To save fuel — and make the trip more pleasant for your passengers — coast to stops and press gently on the gas pedal.

Pay the lowest rate

Find the cheapest gas.GasBuddy,Fuel Finder, AAA Mobile and other apps display gas prices at stations near you, enabling you to pull up to the pumps with the cheapest price.

Play the points game. Use reward points to lower your gas costs. Safeway stores for example, offer drivers one point for every dollar spent on groceries. For every 100 points accrued you receive a discount of 10 cents per gallon at participating stations. Use 200 points and get a 20 cent-per-gallon discount, 500 points gives you a 50 cent-per-gallon discount and 1,00 points, the maximum per fill-up, discounts your gas $1 per gallon.

Plan the trip

Pick a centrally located lodging. Forget about staying in the suburbs when visiting a city. Instead, pick a downtown hotel near the majority of attractions you want to see. Keep the car parked and walk or take short hops on buses and subways. Doing so saves fuel, adds convenience, affords you a local's perspective and eliminates getting stuck in the often stop-and-go traffic between the heart of the city and the hotel in the outskirts.

Consolidate errands. Plan ahead when being helpful. Pick up the pies at the bakery and the batteries for the toys in one shopping trip instead of two.

Use your most fuel-efficient vehicle. Unless you need the space your old, gas-guzzling SUV has to accommodate your spouse, three kids and two dogs, go down the road in the car that gets the best miles-per-gallon.