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5 ways to cut down on rental car gas prices

The offer of a larger rental car at the same rate used to be a happy surprise. But now a free upgrade is bad news, given that a bigger car usually means a giant gasoline bill.

Consumer requests for fuel-efficient cars have spiked this winter, according to spokespeople for Hertz, Budget, and Thrifty rental car chains. In the past two months, fuel prices have jumped 50 cents a gallon, to a national average of $3.77. At and near major airports, it’s often difficult to fill up even a compact car for under $50.

So what to do?

1. Search online for an economy- or compact-car that's fuel-efficient. Budget, for instance, has a page that lists its most fuel efficient cars. Other rental chains do, too. Thrifty recommends its Chevrolet Aveo sedan, which delivers an impressive EPA estimated 25 miles per gallon for city driving, and 34 for highway. Hertz has about 35,000 cars nationwide that are rated at 28 miles-per-gallon or better, though its rates tend to be higher than the national average, unless sometimes when booked in advance.

2. Don't obsess about renting a hybrid. Gas-electric hybrids consist of fewer than 1 in 1,500 cars in the U.S. fleets of the largest chains, which means they aren't widespread enough to rely on routinely. For instance, I tried to book a hybrid vehicle in Chicago through five agencies. For a three-day rental three days in advance, only Alamo, Hertz, and National had hybrids. Chains also tend to charge higher rates for hybrids, which savings at the pump may not offset. Most hybrids tend to be at airport locations, too, where taxes and fees tend to be significantly higher than off-airport rentals. Unless you live in a hybrid-heavy location, such as San Francisco, you may actually save money by renting a fuel-efficient traditional car.

3. Consider pre-paying if you plan to return the car on empty. We know it goes against the standard advice, but at some airports, rental car agencies are pledging that their pre-pay fuel rates are about 20 cents cheaper than the average rate in the airport area. By some estimates, about a third of the time it makes better financial sense to accept the prepaid offer than going to an off-airport gas station. Remember, there's no refund for leftover fuel, so plan ahead.

4. When on the road, seek out cheap gas. Drive a block or two in from the highway for generally cheaper prices. Look for warehouse clubs like BJ's and Costco, which typically sell gas really cheaply and don’t require you to be a member to fuel up. Use gas-station price-monitoring free apps like Cheap Gas and websites like Gasbuddy to check out local rates near your rental car location. AAA's TripTik planner includes a map of your route with relevant gas stations and their rates. Google and Mapquest maps also often have an option you can check to show a layer with gas station locations on maps you print out.

5. Ease off the pedal. Autos are at optimal fuel efficiency when driven at about 55 miles per hour. Go up to 65 mph for any length of time and you'll pay roughly 20 cents a gallon more at the pump at current rates.

This story originally appeared on Budget Travel.

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