Dear EarthTalk: Summer is near and I am planning a big road trip. Do you have any tips for boosting my car’s fuel efficiency on long, hot drives?
—Esther McCoy, Burlington, VT
Ah, the summer road trip, that classic American experience. But long drives through steamy weather can burn through a lot of gas and cause untold wear and tear on your car’s engine and systems while putting you at risk for overheating. Doubling down on tactics to help your car run better will not only improve fuel efficiency, but could also help you avoid spending a large chunk of your vacation time in the breakdown lane waiting for a tow.
According to the American Automobile Association (AAA), there are lots of ways to conserve fuel on hot weather road trips that also will help prolong the life of your car. “In summer, drive during cooler parts of the day,” reports the group. “Cooler, denser air can boost power and mileage.”
While it may seem counterintuitive, using your car’s air conditioning is actually a smart idea in hot weather. “Today’s air conditioners create less drag on the engine than driving with the windows open,” says AAA. Meanwhile, if you have a hybrid, pre-cool it before you get in so it can devote more electricity to driving when you are out on the road. But don’t warm-up (or pre-cool) a conventional car, as the extra idling doesn’t do the car any good and just wastes fuel and creates extra heat. Another key tip for hot weather driving is to park in the shade when you can.
The Green Car Reports website suggests utilizing cruise control and overdrive features on cars that offer them on long summer roads trips; these features help normalize the energy demands of the engine which in turn helps conserve fuel.
According to AA1car.com, a leading online information resource on auto repair and maintenance, placing a sunshade under the windshield and cracking the windows when parked can help keep the interior cool between drives. This can also “lighten the cooling load on the air conditioner when the vehicle is first started.” The website also reports that changing old dirty motor oil with a fresh higher viscosity one will help keep your car’s engine lubricated and running smoothly on those summer road trips. “For example, you might want to change from 5W-30 to 10W-30, 10W-40 or 20W-30 for hot weather driving,” reports AA1car.com. “Synthetic motor oils are even better for high temperature protection.”
Of course, some fuel saving tips apply any time of year. For instance, jackrabbit starts are a big no-no; drivers should always try to accelerate gradually. Taking your foot off the gas as early as possible when approaching a red light is another way to save gas. Keeping filters clean, maintaining recommended tire pressure and driving at the speed limit are additional ways to conserve fuel, reduce emissions and treat your ride nicely.
Of course, summertime road trips can also be hard on drivers and passengers, so pack plenty of sunscreen — especially if you plan to have the windows open (or top down)—and bring along a cooler with healthy drinks so everyone can stay hydrated.