Used 2012 Jeep Grand Cherokee SUV

If the words "160-mph Jeep" don't raise a few hairs on the back of your neck we suggest you have your hair-raising reflexes checked. Because anyone who has driven a Jeep in the last 50 years recognizes that the brand isn't known for building vehicles that thrive at triple-digit velocities.

Until now.

Although we didn't witness the full 160-mph capability of the 2012 Jeep Grand Cherokee SRT8, we did experience the insane SUV at full crack on Willow Springs Raceway, where we were able to corner the beast at more than 100 mph. And based on that quite dynamic experience, we find it likely that the new Jeep is a snoozer at 160 mph while traveling straight.

This, then, hardly seems like a Jeep at all.

Hauls the Mail
After all, what other Jeep have you cornered at 100 or so mph and — dare we say it — felt comfortable? The answer, for us at least, is none. Sure, the first-generation Grand Cherokee SRT8 was a serious machine. It made no apologies for being what it was — loud, fast, brash and, well, stiff as hell.

And this truck is also stiff. Even in Auto mode, where its adjustable suspension can choose its softest settings, it will, occasionally, rattle your fillings. But overall, the ride is compliant enough for daily use — even for our mother.

Yet here, in Turn 8 on Willow Springs Raceway, this thing is confident. Sure, it took us a few laps to adjust to the Jeep's height, which inevitably produces more pitch and yaw than a car, but we rapidly calibrated to its body movement and discovered that this beast sticks with pit bull determination.

The trick is to use the throttle at unorthodox times. This is not a textbook handler. Despite, or perhaps because of, the fact that 65 percent of the available torque is going to the rear wheels in "Track" mode, the Jeep encourages midcorner adjustments with the throttle. And, near as we can tell, it won't make you pay with any unpleasant surprises. It's as stable as it is stubborn.

If there's anything that should shake our confidence it's bending a near 70-inch-tall, 5,150-pound SUV into a corner at more than 100 mph, but after a few laps it's just routine — almost as if this is an act physics can accept.

Target: Germany
Talk to Jeff Roselli, the 2012 Jeep Grand Cherokee SRT8's lead development engineer, and it doesn't take long to figure out why the hairs on the back of your neck are standing proud. Among the litany of obscure facts Roselli offers are these: Its from-the-factory alignment includes 1.6 degrees of negative camber up front and 1.3 degrees out back. Its brakes, 15-inch rotors and six-piston Brembo calipers up front are the biggest in the SRT lineup — including those on the out-of-production Viper. Also, its steering ratio, at 17.5:1, is considerably quicker than that of a standard Grand Cherokee (variable, 18.9:1 on center).

It's almost as if the use of Chrysler's new 6.4-liter V8 is anticlimactic. Trust us, it is not. Although this is the same mill you'll find in every current SRT product, the 470 horsepower and 465 pound-feet of torque it porks out is not to be overlooked. Those figures are 50 hp and 45 lb-ft better than the 6.1-liter V8 it replaces. Chrysler's five-speed automatic transmission is still used and is still merely adequate at best.

And perhaps not so surprising is that the SRT team benchmarked BMW's X5 M as well as the outgoing Grand Cherokee SRT8 in the development of this SUV. Roselli says the Grand Cherokee platform is, in his opinion, a better starting point for a performance SUV than the X5. "It's an incredibly stiff platform," Roselli says. With 146 percent more torsional stiffness than the outgoing model, Roselli's team didn't need to add any additional bracing for the SRT version.

He acknowledges that the X5 M is a faster vehicle in a straight line because of its power advantage but, says Roselli, "The WK [Grand Cherokee] is a better-handling car than the X5 M. The Grand Cherokee — because it's an SRT product — can have its stability control fully defeated, which gives it a significant handling advantage." Also, he adds, "We've got more low-end torque. The WK will whip the X5 M through a slalom or in an autocross." Excellent news for those of you planning to autocross your 2.5-ton SUV.

"The Grand Cherokee is more brash, more involving," according to Roselli. "You can run it more out of shape and it doesn't mind."

Serious Driving
In the end, we discovered, Roselli is right. We've tested BMW's X5 M and X6 M twins and found their nondefeat stability control systems to be truly invasive when driving hard. And the Grand Cherokee, with its sophisticated torque split — 100 percent of the drive torque can be sent to one rear wheel — is superior in the dry. Although we didn't experience it, we'd wager — and Roselli confirms — that in limited-grip driving there is no contest.

Partially, this is because the X5 M comes with standard three-season tires and the 2012 Jeep Grand Cherokee SRT8 comes with all-season Pirelli Scorpion Verde rubber. Three-season Pirelli P Zeros are optional. Both are sized 295/45ZR20.

Its five-mode Selec-Track system (not to be confused with the SelecTrac four-wheel-drive system used in the Liberty) integrates with all systems that can affect performance — stability control, suspension damping, shift logic, torque split, rear LSD operation and more. Largely, its management of torque split and suspension damping yield the biggest influence in control.

Still, if you plan to stomp this Jeep around your back roads or a racetrack you'll find some shortcomings. First, its gear spacing is too wide. Chrysler's five-speed is aging, and even when backed by an engine with this much torque, the gaps between its gear ratios are too big. We found ourselves wishing for a ratio between 2nd and 3rd gears as well as 3rd and 4th gears, both on the street and on the track. The eight-speed automatic Chrysler will begin using in other vehicles this fall will solve the problem if it can be made to accommodate this much torque.

Furthermore, the five-speed box doesn't rev-match downshifts in Manual mode. Sure, there's a downshift paddle on the steering wheel, but request a downshift while under heavy braking and you'll find yourself with unneeded engine braking as the transmission attempts to make the engine speed match the wheel speed. It's as mechanically unappealing as it is dynamically disruptive.

This, according to Roselli, is a "Chrysler Safety Office" item. Translation? Blame the lawyers. Chrysler's policy is to refuse to open the electronic throttle unless a request for more torque has been made by the driver. Enthusiast driving be damned.

Reality Check
But let's get real. This isn't a vehicle most owners are going to take to the track. Heck, it's probably not one most are going to drive hard on their local twisty roads. This is a toy for hauling the family but one that is as engaging to drive as many sports cars. It's an all-wheel-drive sedan on a double dip of amphetamine with trucklike visibility and a 5,000-pound tow rating.

And there's not much that can beat it across an intersection. Jeep claims a 0-60 time of 4.8 seconds, a quarter-mile time in the mid-13-second range, 0.90g on the skid pad and 60 to zero in 116 feet. We ran an impromptu test on the media drive without the benefit of our usual test facility and discovered that, in fact, this Grand Cherokee might be slightly slower than its predecessor. Under less-than-ideal conditions and on a non-standard surface, our acceleration times were off the pace set by the old Grand Cherokee SRT8. According to Roselli, the two should run neck and neck. We'll wait for a full instrumented test at our usual location before leveling a verdict.

But when it comes to fuel economy, well, the verdict is in. This Jeep is no Prius. Even though there's a new active exhaust valve that allows cylinder deactivation over a wider range (a 13 percent fuel economy improvement on the highway), the EPA says the new Jeep is good for only 12 city and 18 highway mpg.

Final Details
At the end of the day it's not just stomping the gas that makes the new 2012 Jeep Grand Cherokee SRT8 special. Its interior is a combination of leather and suede, with deeply bolstered heated and ventilated seats and a meaty steering wheel. Interior quality is a notch behind its German competition, but its MSRP, at $54,470, is nearly $32,000 south of the X5 M and about $52,000 less costly than the Porsche Cayenne Turbo. And that counts for something.

Four options are available: The Luxury Group adds a leather dash, power liftgate and adaptive cruise control. Three-season tires and a sunroof can be had separately. Also, there's an 825-watt Harman Kardon audio system with 19 speakers that sounds better than, well, the last chichi audio system we heard, which featured only 630 watts and 14 speakers.

We'll admit that a 160-mph Jeep capable of out-autocrossing German competitors costing 60 percent more might not be on the top of your need-to-have list. But any Jeep capable of bristling your neck hairs like this will, we guarantee, be on the top of your want-to-have list.

It's now on ours.

Edmunds attended a manufacturer-sponsored press event to facilitate this report.