2014 Jeep Grand Cherokee, SRT at the 2013 Detroit Auto Show

• Competes with: Audi Q7, Land Rover Range Rover Sport, Volkswagen Touareg
• Looks like: A bevy of significant upgrades that don’t mess with success
• Drivetrain: 290-hp, 3.6-liter V-6; 360-hp, 5.7-liter V-8; 240-hp, 3.0-liter diesel V-6; or 470-hp, 6.4-liter V-8 (SRT); eight-speed automatic; rear- or choice of three 4×4 systems
• Hits dealerships: First quarter 2013

With its most substantial update since this generation’s debut for the 2011 model year, the 2014 Jeep Grand Cherokee boasts a new transmission, exterior and interior tweaks, an optional diesel engine, much needed tech improvements and a new trim level. The SRT performance model also receives some welcome upgrades.

More 2013 Detroit Auto Show Coverage

The Grand Cherokee’s styling has aged well, so the 2014’s changes are subtle: The grille is shorter, the headlights slimmer and the bumper has been raised. There are now LED daytime running lights and the fog lights are more prominent. The taillights have gotten larger, and Jeep says it redesigned the liftgate to improve rear visibility.

Greater changes come in the new Summit, which is appropriately named as the top trim level above Overland. It gets unique headlights, grille, 20-inch wheels and brightwork that wraps all the way around the car. It also gets the SRT performance model’s rear spoiler and a distinctive rear bumper.

The 2014 SRT itself is virtually devoid of chrome outside and has blacked-out headlights and taillights.

The Jeep Grand Cherokee is the latest among the Chrysler Group’s models to receive an eight-speed automatic transmission, which is claimed to boost highway mileage by 2 mpg to 25 mpg for the 3.6-liter V-6 and 1 mpg to 21 mpg for the V-8 (rear-drive versions). The tow rating jumps 24% to 6,200 pounds. When teamed with a two-speed transfer case, the new transmission also lowers the off-road crawl ratio by 14% to 44 to 1. Three 4×4 systems are available.

A new 3.0-liter diesel V-6 will produce 240 horsepower and 420 pounds-feet of torque, giving the diesel option the highest mileage — a claimed 30 mpg highway — up to 730 miles of range and the maximum towing capacity of 7,400 pounds. The diesel will be priced above the V-8.

The SRT gets the new transmission, too, complemented by various settings like Track mode, which now sends more torque (up to 70%) to the rear wheels. Launch control is another new feature, and the opposite extreme is an Eco mode that’s new on the SRT and the regular Grand Cherokee. The SRT gets its own steering wheel with enlarged shift paddles that are easier to activate.

Interior upgrades include a 7-inch customizable LCD instrument panel and a redesigned center control panel with Uconnect 5- or 8.4-inch touch-screens. The new lushest model, the Summit has leather seats, suede-like headliner and A-pillar treatments, open-pore wood trim and optional copper-colored accents.

The Grand Cherokee adds active safety features such as rear cross-path detection and radar-based forward collision warning with crash mitigation.