Changes to the redesigned 2018 Jeep Wrangler JL that help improve fuel economy include more gears in the transmission and greater use of lightweight materials.

A new 2.0-liter turbo-four engine, more gears in the transmission, close attention to aerodynamics and greater use of lightweight materials helped give the redesigned 2018 Jeep Wrangler JL a nice bump in fuel economy.

The new-generation Wrangler, which uses aluminum on the doors, hood and tailgate, and has a more steeply raked windshield, carries an EPA rating of 23 mpg city/25 highway/24 combined for four-cylinder models with an eight-speed automatic transmission.

The best the outgoing Wrangler could post was 17 city/21 highway/18 combined, which was for the V-6 model; a four-cylinder engine was unavailable.

The 2018 Wrangler with a 3.6-liter V-6 and six-speed manual transmission also posts higher fuel economy, at 17 city/25 highway/20 combined.

The fuel economy ratings were announced last week.