Jeep never stays in its own lane.
That's not only a consequence of its characteristic off-road capabilities. It also describes the company's approach to vehicle development.
A case in point is the 2014 Grand Cherokee, which has been subjected to an unusually comprehensive mid-cycle overhaul.
Because a fickle buying public quickly becomes blase about any new vehicle, manufacturers try to inject a dose of newness half way through a model's life cycle. Often it consists of little more than a couple of sheet metal changes, additional colors or different equipment packages identified by a new model designation.
But the 2014 Grand Cherokee goes beyond that. There are interior changes that include a new steering wheel, revamped center stack with new touch screens, standard paddle shifters and a programmable instrument cluster.
Outside tweaks include bigger taillights with light emitting diodes, LED running lights, restyled grille, dual exhaust pipes and a larger rear spoiler.
That's the usual mid-cycle stuff. But the Grand Cherokee also comes with substantive changes: new eight-speed automatic transmission with manual shift mode and an economical new diesel engine.
There now are nine GC versions, including a snorting, high-performance SRT model with a 470-horsepower, 6.4-liter Hemi V8 engine with all-wheel drive and the eight-speed transmission. At $63,990, it is the most expensive Grand Cherokee. Performance, including racetrack capabilities, emulates more expensive competitors like the M63 AMG from Mercedes-Benz.
But the heart of the lineup consists of the other eight. There are four trim levels in either rear drive or all-wheel drive: Laredo, Limited, Overland and Summit. Three engines provide the power: 290-horsepower 3.6-liter V6; 360-horsepower 5.7-liter V8, and a new 240-horsepower 3.0-liter V6 diesel.
The diesel delivers 420 pound-feet of torque, or low rpm twisting force. It gives the Grand Cherokee the grunt to tackle virtually any off-road situation, with the main limiting factor the approach and departure angles. This is, after all, a wagon that is nearly 16 feet long, not a rock-hopping Jeep Wrangler. At the off road introduction, front bumpers were removed to improve the approach angle.
Like other modern diesels, the Grand Cherokee's goes about its business unobtrusively. It starts instantly, and idles and cruises quietly. Unless they are informed in advance, few people would even know they were driving an oil burner.
The upside is a surge off the line and characteristic diesel fuel economy. On the tested 5,375 pound Grand Cherokee with all-wheel drive, it had an EPA city/highway mpg rating of 21/28 miles to the gallon. With rear drive, the rating is 22/30. The latter works out to a driving range of 730 miles.
The diesel is a $2,300-$4,500 option, depending on the model, but is not available on the $29,790 base Laredo. Towing capability is rated at 7,400 pounds.
A new wrinkle on some of the all-wheel drive models is a hill ascent feature. Many all-wheel drive vehicles now come with hill descent, which automatically controls the vehicle's speed on steep downgrades off road. The new Jeep system also chugs uphill with acceleration and braking automatically modulated. Unfortunately, the system was available only on V8 gasoline models.
All of the new Grand Cherokees with all-wheel drive come with a system Jeep calls Selec-Terrain, which consists of five choices for maneuvering on different surfaces. There's an automatic mode, along with settings for sand, mud, snow and rock.
The tested Grand Cherokee was the top line Summit with all-wheel drive and the diesel engine. With an as-tested price of $56,990, it was outfitted as well as many luxury cars, including a power rear lift gate, remote starting, automatic leveling bi-xenon headlights, 20-inch aluminum wheels, full-size spare wheel, rain-sensitive windshield wipers, memory power driver's seat, heated leather seats, power tilt-and-telescoping steering wheel, wood interior trim, and wood and leather steering wheel.
It also had full safety equipment, including adaptive cruise control, collision warning, rear backup camera and cross-traffic detection, hands-free communication, and navigation displayed on an 8.4-inch touch screen.
On the road, the tested Summit diesel cruised serenely, with little intrusion of wind, mechanical or road noise. The steering exhibited a solid on-center feel, although the high-performance SRT model's steering was a trifle wiggly in straight-line cruising.
Comfort for four was first cabin although, as is usual in the vast majority of vehicles these days, the center-rear passenger is disrespected with an unyielding, uncomfortable perch.
Model: 2014 Jeep Grand Cherokee Summit 4X4 four-door sport utility vehicle.
Engine: 3.0-liter V6 diesel, 240 horsepower, 420 lb.-ft. torque.
Transmission: Eight-speed automatic with manual shift mode, two-speed transfer case and full-time four-wheel drive.
Overall length: 15 feet 10 inches.
EPA passenger/cargo volume: 105/36 cubic feet.
Weight: 5,375 pounds.
Towing capability: 7,400 pounds.
EPA city/highway fuel consumption: 21/28 mpg.
Base price, including destination charge: $51,990.
Price as tested: $56,990.