, Sun, 19 Apr 2015 02:20:19 PDT
CHELSEA, Mich. -- On a blacktop race track at Chrysler's Michigan vehicle test facility, the go-pedal goes down on a 2015 Grand Cherokee SRT sport utility vehicle and the muscle of some 475 ponies stampedes the world's fastest Jeep into a fast-lane frenzy.
We're talking too quick: The super-souped Grand Cherokee SRT, outfitted with a big-block HEMI V8 and the suspension dropped an inch on sport-taut springs, zips from zero to 60 in less than five seconds, then passes the quarter-mile post in 13 seconds plus change.
The unusual Jeep performs like a raucous sports car but carries a boxy back bay under the thin disguise of a practical sport utility wagon.
This story begins with Jeep's flagship Grand Cherokee, which represents the original sport utility vehicle and traces for decades in Jeep history with innovations like the Quadra-Trac automatic full-time 4WD system in 1973, and a watershed design in 1984 for the first unibody SUV.
The nameplate of Grand Cherokee emerged in 1992 attached to a new wagon which showed that a SUV could conquer rugged off-road challenges and still transport riders in comfort due to cushy cabin appointments. A larger version appeared in 1999 with a luxurious cabin plus mechanical systems which raised the bar for SUV performance, while the 2005 Grand Cherokee with a stronger structure and multiple engine options established even higher benchmarks.
But Jeep rolled out the Grand Cherokee of 2011 and everything about the redesign seemed fresh and better and bigger with a wagonload of new features. Then Jeep's top-dog SUV for 2014 scored a sheetmetal face-lift and gained a wagon-load of high-tech electronic controls plus a new ZF 8-speed electronic automatic transmission.
Meanwhile, some gearhead gurus at the Street and Racing Technology (SRT) division of Chrysler requisitioned a Grand Cherokee and beefed it up with their retinue of high-performance car tricks. Result of these experiments becomes the street-legal 2015 Grand Cherokee SRT.
The SRT initials mark high-performance vehicles for Chrysler and Dodge and Jeep.
Grand Cherokee SRT of 2015 totes a larger and more powerful yet fuel-efficient big-block HEMI engine, a Bilstein adaptive damping suspension with selectable suspension tuning for world-class ride and handling, a flat-bottom heated steering wheel with paddle shifters for hands-on-the-wheel shifting, plus a new Torqueflite ZF 8-speed electronic automatic transmission with rev-matched downshifts, Launch Control and driver-choice shift modes: Drive/Sport/Eco.
Heart of the SRT Jeep make-over is that big-block HEMI engine: The 6.4-liter HEMI V8 kicks out 475 hp at 6000 rpm plus 470 lb-ft of torque at 4300 rpm.
It comes with standard Fuel Saver Technology (FST) which can switch seamlessly and transparently to a fuel-saving 4-cylinder mode when all of that horsepower is not needed for romping. Premium 91-octane fuel is recommended for the SRT Jeep and the estimated fuel economy figures tally to 13 mpg city and 19 mpg highway.
The SRT SUV stocks Jeep's Quadra-Trac active on-demand 4-wheel-drive transfer case. The device lets a driver dial in one of four torque-split settings (40/60 Auto, 50/50 Snow and Tow, 35/65 Sport and 30/70 Track) then the system tailors the vehicle's traction performance to fit the type of terrain covered by modulating powertrain response, transmission gear selections and electronic controls.
SRT engineers worked on the Grand Cherokee SRT suspension. They lowered it by half an inch and tuned it tightly for performance with tailored spring rates and bushings, big anti-sway bars in place plus anti-skid controls via an electronic stability control device.
To rein so many horses, the 20-inch wheels on Grand Cherokee SRT carry big disc brakes. Up front, the 15-inch rotors team with Brembo 6-piston calipers painted red. Rear ones with 13.78-inch rotors get Brembo 4-piston calipers. All four discs are linked and controlled through an anti-lock brake system plus traction control system.
The 5-seat passenger cabin skews to techno mode with trimwork in carbon fiber and seats in fine leather. Appointments include Active Noise Cancelling technology and the Uconnect touchscreen display showing a wealth of SRT-exclusive Performance Pages, including recent track times, lateral acceleration, 0-60 mph times and much more.
Jeep builds a more powerful and more sophisticated 2015 Grand Cherokee SRT with price points starting at $64,595.