Consumer Reports testers use a fuel meter to put several cars through their paces at 55, 65, and 75 mph. Though it may not be surprising that when you drive faster, you use more fuel, you may be surprised about how much fuel you actually use.
Take a four-cylinder Honda Accord LX:
• 55 mph — 50 mpg
• 65 mph — 42 mpg
• 75 mph — 36 mpg
Consumer Reports also tested the Toyota RAV4 and three versions of the Ford Fusion, including the hybrid, and found similar results with all of them.
Loading your car for road trips also cuts your fuel efficiency. So does adding a bike rack. By how much, you may wonder. Remember the Honda Accord at 65 mph getting 42 mpg? With a bike rack, fuel efficiency drops to 37. Add a wind deflector, and surprisingly it drops again, to 35 mpg. Now add two bikes and the mileage sinks to 27 mpg.
So if you’re not using your bike rack, take it off because it really is going to hurt your fuel efficiency. A lighter load and a lighter foot on the pedal definitely add up to savings at the pump.
A rooftop luggage carrier can also cut your fuel efficiency. Consumer Reports says you can lose up to 6 mpg with one of those on top of your car. So take it off if you aren’t using it. And to get the best mileage possible, make sure your tires are properly inflated.