Illustration showing two types of bike racks: a roof rack (left) and a hitch rack (right)
Illustration: Rodrigo Damati

Roof and trailer-hitch racks are great at toting your gear for a weekend adventure, but those mounts can change the aerodynamics as well as the weight of your vehicle—costing you additional gas money.

More on Bikes & Fuel Economy

To find out just how much of an impact they have, our experts measured how different car racks—when empty and when loaded with two adult-sized bicycles—affected the fuel economy of a 2019 Nissan Altima sedan and a 2019 Toyota RAV4 small SUV going 65 mph.

For the sedan, our tests revealed that the fuel economy took a significant hit with a loaded bike rack (much more than the SUV’s)—and even the empty roof rack exacted a large fuel-economy penalty. Only the empty hitch rack had a negligible impact.

The RAV4 SUV, on the other hand, was less affected by either rack type, but the hitch was still the clear winner.

A hitch rack is also easier to remove—which will help encourage you to take it off when you don’t need it, and save fuel no matter what vehicle you drive.

Reduction in MPG