Climbing a 65-degree mountain face isn't something your average vehicle can do. The Jeep Wrangler does it with little effort mind you, but to see a line of Jeep Grand Cherokees follow one up the 300-foot granite wall known as Moab at Ink's Ranch near Llano, Texas sounds like a bit a of a stretch. From the bottom of the hill, it would seem an impossible task. A few deep breaths and a quick Hail Mary later, the fear and doubt turns to excitement and belief as blue sky fills the entire front windshield of my pre-production test mule. Adrenaline courses through my body as the 2,393-kilogram Overland EcoDiesel clambers steadily up the steep incline before we crest and turn to head back down.

Getting to the top is a piece of cake really. The Moab face doesn't just look more dangerous from up here, it is more dangerous. Surely the rocky gulley at the bottom has collected its fair share of victims in the dozen or so years the Jeep Jamboree USA has been coming here to play. But not on this day. Getting down from this precarious perch couldn't be easier actually. All I do is press the hill descent control button on the centre console and steer. A multitude of sensors and some serious computing power takes over control of the brakes and differential, and the Jeep does the rest! Had I not tried this myself and gotten the bottom safely and feeling exhilarated, I might not have believed it.

Moreover, had I attempted this seemingly impossible task with one of the 5.7L V8-powered models Jeep had on hand for the launch of its 2014 Grand Cherokee, I could have used the hill control feature to ascend this obstacle without my right foot ever touching the gas pedal as I did over on the Homestead Trail at Ink's Ranch. That in and of itself is a pretty cool experience! The fact the new Grand Cherokee can do all this without live axles and disconnecting sway bars is impressive. And thanks to its Selec-Terrain and other related features, I'm now more sure of its capabilities both on-road and off.

Grand Cherokee has the goods

As fun and cool as the off-roading is, the main reason I'm in Texas is to drive the latest SRT version of the Grand Cherokee on the all-new Circuit of the Americas Formula One race track. Bah, that's heresy! Not! Despite losing the “8” from its badge – no doubt to set the SRT brand up for a future where engine size is not what it's all about – the 2014 Jeep Grand Cherokee SRT has reached the next level.

“Tuning has changed in this day and age,” says Ralph Gilles, President and CEO, SRT Brand and Motorsports. “We're all about performance and it's no longer just about horsepower, it's about how to take all that cool technology, which is also in the base car, all those programs, all those controllers and making them all work in a synthesized way to bring the capability of this vehicle to incredible levels.”

The V8 engine is the same impressive 6.4-litre Hemi job with 470 hp and 465 lb-ft of torque the outgoing '12 model I drove last summer was packing, but that's where the similarities to the new powertrain stop. The old five-speed unit is replaced by a new eight-speed automatic transmission with paddles and an electronic shifter. This transmission has completely changed the character of the vehicle, which still boasts an incredible symphony of complementary technology.

To improve the overall experience for driver, the monostable shifter has a standard drive position that you bring the car into. In the default mode, the shifter controls only the transmission, and the suspension settings remain unchanged. But, if you're driving along in auto mode and want to have more sporty gear changes, you pull the lever back to set it in sport shift mode – as indicated by the 'S' up on high-res seven-inch TFT instrument cluster. This results in quicker rev-matched downshifts to help slow the car down, it holds gears more for better cornering and it makes for a real nice sporty shifting mode. Sport mode also shuts off the Hemi's fuel saver multi-displacement system (MDS) so the vehicle is very responsive all of the time.

The transfer-case has been modified so as to interface with the new eight-speed transmission, which can hold up to 99 different calibrations, while the electronic limited slip differential has also been modified and strengthened to increase towing capacity by 44% to 3,265 kilograms (7,200 pounds) over the outgoing model. “We don't add the 44:1 crawl ratio or two-speed transfer-case,” clarifies Chief Engineer, Dave Cotrell. “Those aren’t things this (SRT) customer needs, but we do use Quadra-Trac to move power all around this car.”

Delivering the goods your way

Located on the centre console, the Select-Track control knob allows access to five active suspension modes: track, sport, auto as well as the snow and tow modes. Track and sport modes change the dynamics of the car quite considerably, but the Grand Cherokee SRT lets drivers have their cake and eat it too. Let's say you don't want to have that real sporty shifting, you just want to a sport suspension. No problem. “Select-Track gives us all these different capabilities in order to manage all that,” explains Cotrell. “You can have the shifter in 'D' while still having a nice firm sport suspension whether you're in sport or track mode – the latter of which has a very stiff suspension.”

Of course, the vehicle is always in all-wheel drive mode, but SRT has done a number of things with the transfer-case that affect the proportioning. In auto mode, for example, the system operates with a 40% front, 60% rear bias. Slip it over to sport mode and you now get a firm rebound in the suspension – that makes the car feel like it's getting sucked down in to the road – with 35% in the front and 65% in the rear for a little more rear-wheel drive bias. Switching over to track mode, that bias becomes 30% front and 70% rear, and the suspension is locked into full firm mode – there's no more adaptive suspension; compression and rebound  are locked into full firm.

“The only way it will come out of that is if you come wheelin' into a corner with a bunch of bumps in it and the car starts moving around a whole lot (we have accelerometers in the car that know when that is happening) the suspension would release and keep the tires on the ground,” he adds. “Once you make it to the outside of that turn, the suspension goes back to full firm – you never knew it happened, but you made it through the corner like a hero.”

In snow or tow mode, the bias is set at 50/50 all the time. The difference between them, however, is that snow mode follows very strict ESC calibrations for snow and ice. Tow mode uses a pretty much standard ESC calibration, however it tweaks the suspension settings so you won't get any of that bouncing around when you have a heavy load out back.

“The vehicle had the ability to run in Eco mode so we do have an 'Eco' button,” Cotrell points out. It may sound weird for a SRT to have an Eco button, but it has helped to increase the fuel economy of this car – a net improvement of six percent according to SRT. “We didn't want to miss out on that because we had the capability in the vehicle,” he adds. It's actually quite nice for driving around town – it starts in second gear, it has a different shift calibration that kind of softens up the car from a drivability standpoint.

All of these hardware and software bits combine to provide a package that can be set up for almost anything you want it to do. About the only thing you wouldn't want to do with this truck is to take it off-roading. Fortunately, there are plenty of other Jeeps for that and, in fact, the Grand Cherokee is certainly on the list. Any of the other models – ranging from the base to Limited V6 and V8 to any combination of the Summit and Overland models (only the last two can be had with the new EcoDiesel by the way) – are willing and able to act on that particular request.

Austin we have lift off

SRT has been quite successful in taking the “tractive capabilities” of the new Jeep Grand Cherokee and using them for traction, for acceleration and for braking on its version of the vehicle. Add to that four 295-mm sticky tires that provide all the on-road traction you'll ever need. But there is one other performance treat in here not to be overlooked – the button labeled 'Launch' right next to the Select-Track control knob. That's the fun button! Push it and the vehicle is automatically set up for maximum acceleration. The ECU advances the cams and the transmission goes into a special shift calibration called “A-max shifting” with no torque cut between shifts. The t-case is now set at 30% in the front, 70% in the rear and the LSD programmed for traction to both tires, so there is no shortage of traction as the weight transfers rearward under maximum acceleration. The vehicle can still creep too. If you're trying to stage at the drag strip, for example, you can creep up to the staging lights with the system still ready.

It works like this: Once launch mode is engaged and the vehicle comes to a full stop with the steering wheel straight (the system will tell you to straighten if it isn't already), the driver mashes both the brake pedal and accelerator, which is preset to 2,000 RPM at wide-open throttle, and has five seconds to dump the brake and take off like a rocket on a string. And when you get off the gas, it goes back into whatever mode you were in, including Eco mode.

SRT claims the truck does zero-to-100 km/h in 4.8 seconds, but I've seen evidence it can do it a half-second quicker. Stopping completely from 100 km/h takes 35 metres (115 feet). The truck can pull 0.9 Gs on the skidpad, runs the quarter-mile in the 13s and tops out at 257 km/h.

Pouring on the awesome sauce

As it were, the 2014 Grand Cherokee SRT eats up the 20-turn COTA F1 track like Cookie Monster does chocolate chip cookies – nom nom nom! Gearshifts are so smooth and seamless, the chassis so firmly glued to the tarmac you'd swear this is no SUV. Tooling around on the street, the SRT V8 operates at a very low RPM and produces a nice, deep sound. Out on the 5.47-km (3.4-mile) long track, however, it operates at very highs RPMs and stays in the powerband more where it barks out a fearsome exhaust note. It is no ordinary SUV.

With Select-Track set to track mode and the shifter in Sport mode, it climbs the hill into turn one confidently, even after braking late for the late apex that helps carry speed through the more flowing corners two through five. Carrying too much speed through five can produce understeer and make you late fox six, seven and eight, but this is the slowest part of the track anyhow so sacrificing some speed through here somewhere helps set up for a good run out of nine, through 10 and down the hill into 11, which spills out on to the longest and fastest part of the track.

The SRT V8 and full-time 4x4 system help propel the monster truck to speeds above 210 km/h (130 mph) at the end of the very long back straightaway where the massive Brembo brakes are being put to the test. The 380 mm vented front rotors with six-piston calipers and solid 350 mm rear discs with four-piston calipers have proved they can take some serious abuse too, though do show signs of wear from a week's worth of being thrashed on by waves of varying degrees of lead-footed journalists.

Those chunky Pirelli P-Zero tires and SRT Bilstein sport suspension prove their worth through the tight and technical turns 12 through 19 where the chassis demonstrates good balance and composure. Though not lightweight by any means, not once does the SRT Jeep feel top heavy. Not even at the edge of the wide run-off zone coming out of the final corner and that final drag race to the start/finish line – it is the stuff dreams are made of. Well done SRT. Bravo.

And then some

The Viper-like vented hood, chrome-trimmed black front grille, projector fog lights and SRT-exclusive adaptive Bi-Xenon headlamps look absolutely sinister and give it a really unique demeanor though much of the sheet metal is standard. Unique taillights, a rear diffuser with dual integrated four-inch exhaust tips and several wheel choices are nice touches.

Its good looks are not skin deep. The SRT cabin is well-appointed with heated and ventilated Nappa leather-faced seats and a flat-bottom performance steering wheel the likes of which would not look or feel out of place in an Audi or Porsche.

The 8.4-inch Uconnect screen is something to be really excited about. It now has the SRT performance pages incorporated into it (these are also tied to the seven-inch TFT instrument cluster) to access things like zero-to-60 timers, eighth-mile and quarter-mile timers, braking distance, G-forces meters and more. Not only can you record and play back this data, you can now save save it to a USB drive or SD card. Another fun feature of the Uconnect system lets you upload to the “cloud” and share with your friends from inside the vehicle.

One of the coolest SRT pages is the engine screen, which displays real-time horsepower, torque, running gear and vehicle speed data on the beautiful full-colour touchscreen. If you get caught ripping around town and a local constable pulls you over to tell you how fast you're going, not only can you show him how fast you were going, but also how much horsepower and torque you were using at the time and even what gear you were in. This could get help get out of a ticket, or maybe it'll confirm what the speed gun already recorded, but it's fun to look at nonetheless.

I honestly would love to own one of these trucks, but I fear its appetite for consumption could all but destroy me. The wallet would surely take a hit with expensive fill-ups and ridiculous insurance, and my sparkling driving record wouldn't likely remain that way for long. Everyday fuel economists might seriously consider the EcoDiesel-powered Overland or Summit models for more practical purposes, while those with cake can eat it too in a Jeep Grand Cherokee SRT. Compare all you want with a fully-loaded BMW X5 with M pack, Mercedes-Benz ML63 AMG and/or the Porsche Cayenne Turbo, the SRT gives them all a run for the money.

For exclusive video of the 2014 Jeep Grand Cherokee at Ink's Ranch and the SRT at COTA, visit the PRN IGNITION YouTube channel at youtube.com/prnmag.

Specifications

2014 Jeep Grand Cherokee SRT
Base Price: $62,995
Engine: 6.4L Hemi V8
Horsepower / Torque: 470 hp / 465 lb-ft
Configuration: FA
Transmission: 8-speed automatic
Fuel Economy Ratings: 16.6 / 10.7 / ??? L/100 km (city / hwy. / comb.)

Story by Shaun Keenan | Photography by SRT