2018 Jeep Grand Cherokee Trackhawk First Drive: Fastest SUV Carries a Jeep Badge

A 707-horsepower Jeep answers a question no one asked about SUV performance, and time will tell if it meets a demand no one knew was there. Fiat Chrysler Automobiles is about to start building a batch of 2018 Jeep Grand Cherokee Trackhawks with a supercharged 6.2-liter V-8 engine. There are already orders and handraisers for the limited-run SUV rocket that goes on sale in the fourth quarter.

The Hellcat engine generates 707 hp and 645 lb-ft of torque, distributed through the upgraded TorqueFlite eight-speed automatic transmission. It is billed as the fastest SUV in the world.

Jeep claims it will do 0-60 mph in 3.5 seconds. I did it in 3.4 seconds on my first try. Don’t give me the credit. On this Jeep it is that easy, and the launch is that good.

Put your left foot on the brake, and hold it down tightly. Press the launch button in the center console below the leather-wrapped shifter. Watch the brake pressure build as you watch it rev from 700 rpm to an ideal 1,800-2,200 rpm. The new torque reserve system makes it possible to hold the engine at 2,200 rpm and develop 6.4 psi of boost standing at the line. The system prepositions the supercharger while cutting fuel to individual cylinders and manages the spark timing to generate a reserve of torque.  Essentially, it gets the air moving while you are standing still so it is primed and ready for launch.

Use your right foot to push the accelerator to the floor. Hold both feet steady, and then quickly dump the brake. The front wheels will lift, your helmeted head will snap back, and the 5,300-pound SUV will shoot forward. You will hold on and giggle. You will never feel out of control with the traction that a four-wheel-drive vehicle provides. Engineers say this is why a Jeep can actually launch faster than a Dodge Challenger Hellcat. Jeep officials just don’t do much bragging about it.

Scott Tallon, director of the Jeep brand, reminds us that Jeep has a history of high performance vehicles dating back to the 1998 Grand Cherokee 5.9 Limited that did 0-60 mph in 6.8 seconds and was considered an animal. The first-gen SRT for 2006 did the sprint in 4.8 seconds.

Trackhawk is good for Jeep, Tallon says, as if one of the best-known brand names in the world needed further attributes. But the way he sees it, Jeep has the Wrangler as the poster child for Jeep off-road capability, and the Trackhawk underscores its on-road prowess by exhibiting insane track capability. While Trailhawk denotes best-in-class off-road capability, Trackhawk denotes best-in-class speed. The Jeep Grand Cherokee is the undisputed fasted SUV. For comparison, the third-generation Porsche Cayenne S, unveiled recently, increased its horsepower to 440, though the automaker has yet to debut Turbo and Turbo S variants.

“This is not just an engine swap of a Hellcat into a Grand Cherokee,” Tallon says. The Trackhawk is instrumental in driving the growth of the global brand and rounds out the top end of the lineup.

With so much power, I was expecting the Trackhawk to be a bit raw and brutal in regular driving. That was not the case. The supercharger drive system’s one-way clutch de-coupler improves refinement while allowing the beast under the hood to be heard in guttural growls at low speeds and unleash a series of snorts and pops when you mash the pedal. Those who worked on refinement succeeded. You don’t hear much of the supercharger at tip-in, but the sound increases as you throttle up. Sure the suspension is stiff, but even on a long stretch of rough pavement in Maine and New Hampshire, the Bilstein adaptive damping suspension made the drive quite livable.

The reminder that this has a Hellcat engine comes when you step on the gas to cross a highway, and it lurches forward. Or when you go to pass and grab gobs of power and exceed the speed limit faster than you can check the speedometer. This is one vehicle where current speed should be displayed digitally in giant letters in front of you. The speedometer, located in the lower right of the instrument panel with a traditional needle flitting between speeds listed in 10-mph increments, can make it hard to keep speed in check without setting the cruise control.

FCA claims the Trackhawk will do the quarter mile in 11.6 seconds with a top speed of 180 mph, necessitating a speedometer that goes to 200 alongside the tachometer in the 7.0-inch instrument cluster. The 8.4-inch Uconnect touchscreen is where you find the Trackhawk Performance Pages that confirm your track prowess. The SUV has new six-piston front Brembo brakes (largest standard front brakes on a Jeep) and four-piston rear Brembos with yellow calipers, which bring the SUV from 60 mph to a stop in 114 feet.

We have not had the chance to test these claims ourselves, but we were able to take the Trackhawk to the newly paved Club Motorsports track in Tamworth, New Hampshire. The 2.5-mile track carved out of the forest has 700 feet of elevation changes to spice up the turns. The Trackhawk devoured it all and never felt overly heavy or lumbering.

Back on real roads, the lane assist system was spotty—sometimes it brought the car in line, but other times it would hold a line that was outside the lane marker.

The Trackhawk starts at $86,995, but you can easily option it up to a $100,000 vehicle. The one I drove in Portland stickered at $99,965, about $20,000 more than an SRT. The options included a $5,000 leather-wrapped interior package, upgraded audio and entertainment system, dual-pane panoramic sunroof, and a trailer-tow package. Other upgrades go from the standard 20-by-10-inch Titanium finish wheels with Pirelli Scorpion Verdes all-season tires to the lighter forged aluminum wheels with three-season Pirelli P-Zero tires.

From behind the wheel you look down at the bulging sculpted hood with dual heat extractors. The Trackhawk also has unique quad exhaust tips, a redesigned fascia, unique headlamps, and a flat-bottom steering wheel with paddle shifters. Like the SRT, the Trackhawk is an inch lower than a regular Grand Cherokee. It has body-colored wheel flares, side sill cladding, supercharged badging on the doors and sills, and Trackhawk badging on the steering wheel and seatbacks. Inside, in addition to miles of leather, are nice carbon-fiber and industrial-looking trim pieces.

The supercharged engine has a cast iron block and a forged steel crankshaft with a damper that has been tested to 13,000 rpm to ensure it won’t burst. Everything from pistons to connecting rods, cylinder heads, and exhaust valves are upgraded to handle the extraordinary demand being placed on them by this engine. Many driveline components were engineered to handle the additional torque output. Even a new oil plan was developed to prevent the liquid from sloshing when the SUV launches.

Similarly, the 2,380cc-per-revolution supercharger was designed to regulate boost pressure to 11.6 psi. The foglamps had to be swapped out for a cold-air scoop in the lower front fascia to get more air to the supercharger.

Many of the modifications are to keep things cooled, especially on the track. There is also a new fuel delivery system with two new pumps to feed the demands of the engine. Track is one of five modes, and it reduces transmission shift times by 68 percent compared with the Auto mode and tightens the suspension to firm; stability control, four-wheel drive, and steering are set for track performance with a 30 percent front and 70 percent rear torque split. The other modes are auto, sport, snow and tow.

Off-road capability is not overly compromised just because the SUV goes like a bat out of hell. It has Jeep’s Quadra-Trac, on-demand four-wheel-drive system with an electronic limited-slip differential and a single-speed active transfer case with a wider chain. There is also a stronger new rear axle, and the SUV can tow 7,200 pounds.

The Trackhawk is a global vehicle built at Detroit’s Jefferson North plant on the same line as the rest of the Grand Cherokees. There will be a limited run, but officials are not saying how many that is or if it will be less than the roughly 2,500 Grand Cherokee SRTs Jeep sells a year with virtually no marketing, promotion, or incentives. The Trackhawk Jeep already has thousands of handraisers, Tallon says. The plan is to be able to build enough in the fourth quarter to meet the initial global demand. He would not say how large the U.S. allotment is.

And buyers will not have to sign a letter acknowledging the risks of driving the vehicle, which is the case for buyers of the even more powerful Dodge Challenger SRT Demon muscle car.

The Grand Cherokee Trackhawk might answer a question that no one asked. But the correct answer for enthusiasts is “yes please.”

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