Jeep's fourth-generation 2018 Wrangler JL arrives as a significant update to its Wrangler JK that upgrades the off-road icon into a more connected, fuel efficient, and more configurable model that should be a high-priority target for rental fleets in Utah, Colorado, and other areas located near national parks.

The comprehensive update adds plenty of interior upgrades, new powertrains with a mild-hybrid system and future diesel engine, a redesigned transmission, and easier-to-configure soft top and fold-flat front windshield. The Wrangler JK lasted for 13 model years, and some of the upgrades — especially those involving the interior and connectivity — feel dramatic, while other could be described as polishing a gem stone.

We tested the 2018 Wrangler Unlimited Sahara — the four-door model. Two-door models, which account for about 20% of Wrangler sales, will drop the Limited badging.

Powertrains Expand, Diesel Engine Coming

The Wrangler carries over one of its engines, the 3.6-liter V-6 that makes 285 horsepower, and will adds a turbocharged 2.0-liter four-cylinder later in 2018 that makes 270 hp with eTorque mild hybrid technology. Jeep will add a turbo-diesel 3.0-liter V-6 in 2019.

Transmission choices include an Aisin AL6 six-speed manual transmission as standard equipment or the 850RE Torqueflite eight-speed automatic transmission that debuted in the 2018 Cherokee. We tested the eight-speed, which manages city driving effectively enough.

Fuel economy improves significantly, as the eight-speed gear box replaces a five-speed automatic. The new Wrangler gets an EPA-rated 18 mpg in city driving (up from 16 mpg), 23 mpg on the highway (up from 20 mpg), and 20 mpg combined (up from 18 mpg).

A part-time four-wheel-drive system is standard equipment on Sport, Sport S, and Sahara trim models with Dana front and rear axles. Sahara models offer an optional full-time all-wheel-drive system called Selec-Trac that allows drivers to select an automatic mode. The Wrangler offers a more robust Dana 44 rear axle as an option.

A More Connected Wrangler

The highlight of the update comes when you step inside the Wrangler, especially if you've recently driven a Wrangler JK model as we did almost a year ago. The hardcore Jeep enthusiasts may not need much more than the wind in their hair, but those looking for a bit of comfort should consider the optional 7-inch Uconnect touchscreen infotainment system with Apple CarPlay and Android Auto. For even greater connectivity, the Electronic Infotainment System Group steps up to an 8.4-inch screen with navigation, an Alpine audio system, auto-dimming rear-view mirror, and and roadside assistance with 9-1-1 calling. Even the basic radio, a 5.0-inch color display, is an improvement.

We had trouble locating much more than a single USB charging port in the JK. USB ports are standard across all trim grades (including a USB-C in the front), as are Bluetooth phone connectivity and voice controls. The Sahara offers two 12-volt outlets, an AC outlet, two USB 3.0 ports, and one USB-C connection point.

Pricing starts at $25,440 for the two-door Wrangler and $37,345 for the Wrangler Unlimited. Our tested model would retail for $50,220.

2018 Jeep Wrangler JL Specs:

• Engines: 3.6L V-6 (285 hp, 260 lb.-ft.) or 2.0L turbo inline-four (270 hp and 295 lb.-ft.)

• Transmissions: 8-speed automatic or 6-speed manual

• All-wheel drive: Standard part-time system, full-time Selec-Trac, or Rock-Trac (Rubicon)

• Cargo space: 72.4 cu.-ft. and 31.7 cu.-ft. with second row seating