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Twenty-Grand Cherokee

Written by PFM Staff

A Grand Cherokee for $20K? Right. The price varies state by state or by cooperative bid, but a Grand Cherokee with a Heavy Service package is available in the same general price bracket as the Ford Explorer. Pricing for the Grand Cherokee Laredo 4x4 “Heavy Service” varied from just under $21,000 to just over $22,000 for the 2009 model. The 2010 models will be priced based on the Chrysler reorganization with Fiat. The V-8 version ran from just under $24,000 to just over $25,000.

Chrysler produced police-package, pursuit-rated versions of the Jeep Cherokee from 1995 to 2001. After 2001, the Cherokee was replaced by the Dodge Durango. Turn around is fair play. The Jeep Grand Cherokee is now intended as a replacement for the discontinued Dodge Durango.

After getting over the shock of a Grand Cherokee being less expensive than a Tahoe, and equally priced with the Explorer, most fleet managers have two main concerns regarding the Grand Cherokee: the engine and the center console.

210-hp 3.7L V-6

The Heavy Service Grand Cherokee is powered by a 210-hp, 3.7 L V-6. This compares to the 210-hp, 4.0L V-6 in the Explorer. The 210-hp Grand Cherokee hits 60 mph in 10 seconds and 100 mph in 29 seconds. In comparison, the 210-hp Explorer reaches 60 mph in 10 seconds and 100 mph in 35 seconds.

The Grand Cherokee is electronically top speed limited to 112 mph, and the Explorer is limited to 104 mph. During wide open throttle, the V-6 powered Grand Cherokee does well up to 75 mph, has a bit of a flat spot until 90 mph, then does well all the way to 112 mph. The V-6 Explorer does well up to 90 mph and has a flat spot in performance all the rest of the way to its top speed of 104 mph.

V-8 Upgrade

The Heavy Service package Grand Cherokee is available with a 305-hp, 4.7L V-8 for more demanding scenarios. The $2,797 “Performance Upgrade” includes a 4.7L FlexFuel V-8, heavy-duty engine cooling, Class IV hitch receiver, and a power passenger seat. The 4.7L V-8 is the only Grand Cherokee engine that is E85 compatible.

The Special Service package Explorer is not available with a V-8. It is the retail Explorer that is available with a 292-hp, 4.6L V-8 as an extra-cost option, as is the Grand Cherokee with its 305-hp, 4.7L V-8.

Center Console for Cop Gear

The Grand Cherokee, like the Explorer, has a floor-mounted console shifter. Exactly like the Explorer, an aftermarket center console is available to hold a great deal of police gear. The center console was designed by PDS Police Services and custom made by Mounting Systems of America.

The sheetmetal console measures 9 inches wide by 18 inches long and stands 12 inches off the floorboard. As built, it has the room for a combination of six radios or controllers. At the front of the custom console, there are three 12V accessory receptacles. At the back there are two large cup holders. In front on the cup holders is a perfectly positioned arm rest.

The top surface of the center console could be one to two inches lower. This would make the equipment displays in the console a bit easier to see. This also would make it a bit easier to climb over in an emergency. Of course, the console must be tall enough to house the make and model of communication and enforcement gear being used.
The laptop mounting stand also came from Mounting Systems of America. It is important that this bolts under the seat rails and does not require holes to be drilled into the floorpan. Even when backed up with plates, floorboard-mounted MDT trees always seem to flex the floor. The under-seat mounts are more rigid and, of course, holes do not need to be drilled. This reduces the change of driveline damage during the upfit and maintains the residual value when taken out of service.

Entry and Exit


The Grand Cherokee was easy enough to enter and exit, even with a full duty belt. The adjustment of the tilting and telescoping steering wheel, of course, affects entry and exit. The Grand Cherokee uses the awkward friction lock system, where the locking lever is under the steering column.

This lever is so slow and difficult to reach (to unlock and move the wheel out of the way) that we found a compromise setting. This was a setting where the wheel was positioned mostly OK for entry and exit when wearing a duty belt.

The rear entry and exit is good thanks to a new design of the rear door hinge. Compared to pre-2005 Grand Cherokees, the rear door opens in a much wider arc. The door width is unchanged but the door opening is 8 inches wider. The rear seat room, overall, is only in the Charger-Impala category, but the wider opening rear door is a real plus. The liftgate rises enough for a 6-foot, 4-inch-tall officer to walk under it.

Interior Room

Overall, the driver and passenger space is quite similar between the Grand Cherokee and the Explorer, but the Grand Cherokee has slightly more front and rear headroom. They both have about the same front and rear shoulder room. The Explorer has a slight edge in front and rear legroom.

Critically, the Grand Cherokee has a clear advantage in front space (2 more inches) and rear space (5 more inches) hip room. More hip room is important to patrol officers wearing gunbelts.

The Grand Cherokee has a hand-operated emergency brake lever located along the right side of the driver’s seat on the bottom. No, this is not a good location but, incredibly, it is actually not in the way. The Grand Cherokee seat is wide enough so the brake lever doesn’t take up hip or thigh room. Some officers did not notice the manual parking brake lever until it was pointed out.

Cargo Space

In addition to drivetrain traction and high ground clearance, an SUV is used instead of a police sedan because of the extra cargo capacity. The Grand Cherokee does not have the same cargo capacity as the Explorer. Behind the back seat, headliner to floorboard, the Explorer has a total volume of 45.1 cubic feet, compared with the Grand Cherokee at 34.5 cubic feet.

When measured only below the line of sight (the top of the rear seat or the bottom of the rear glass), the cargo differences between the two vehicles are still significant. With an unobstructed view out the rear window, the Explorer cargo volume measures 33 cubic feet. In comparison, using the same method, the Grand Cherokee cargo area measures 19.1 cubic feet. The Grand Cherokee’s cargo volume almost exactly matches the Ford CVPI trunk.

All-Wheel Drive QuadraTrac I

The Grand Cherokee with the 3.7L V-6 uses QuadraTrac I, which is a full-time, high-range-only all-wheel drive. This is different from the classic two- range 4x4 HI / 4x4 LO systems. With QuadraTrac I, brake traction control shifts the torque automatically between the front and rear axles. It is a front to rear shift only, not a side to side shift.

The all-wheel drive QuadraTrac I is fully automatic. The driver does not have to do anything. In fact, QuadraTrac I has no levers or buttons for the driver to pull or push. This system defaults 52% of the torque to the rear wheels.

During our two weeks with the Grand Cherokee, we got into rain that was heavy enough that most of traffic had pulled over and stopped. The full-time AWD was good to have. Of course, all the rain during our review period made the medians wet, soft and muddy…just what Jeeps were designed for! Jeeps and mud have always been made for one another. Like the Explorer, the Grand Cherokee has electronic stability control with electronic roll mitigation.

The QuadraTrac I is the only drive system available with the 3.7L V-6. However, the V-8-powered Grand Cherokees use either QuadraTrac II or QuadraDrive II. The QuadraTrac II uses the two-speed transfer case for 4x4 ALL TIME and 4x4 LO. In high range, torque is divided front to rear between the axles with 52% to the rear as a default. In low range, the front and rear axles are electronically locked.

The QuadraDrive II uses the same two-speed transfer case but adds electronic limited slip differentials on all four wheels. This system shifts torque front to rear and side to side between individual wheels, not just the front and rear axle. With this system, all of the engine’s torque can be applied to any one wheel.

Heavy Service Package

Any Dodge dealer in the U.S. could have developed the Heavy Service package for the Grand Cherokee, but it was the police fleet-oriented Thomas Dodge that did so, just as it did for the Dodge Durango. The Heavy Service package begins with the base Grand Cherokee Laredo 4x4 and adds some retail options and some dealer special order options. To that techs add some dealer-coordinated upfitting (www.highlanddodge.com).

The Heavy Service package Grand Cherokee comes standard with two features specifically geared to the police use of an SUV: the Trailer Tow package and the Skid Plates package. The Trailer Tow Prep package and the Skid Plate package are extra cost options on the Special Service package Explorer. The Grand Cherokee has 8.5 inches of ground clearance. This compares with 8.3 inches for the 4x4 Explorer.

The Trailer Tow package, in turn, includes a heavy-duty suspension. Jeeps are famous for their off-road suspension, but the Grand Cherokee has been softened a bit for most retail customers. The Trailer Tow package puts the Grand Cherokee back up to Jeep legend status.

The Grand Cherokee has a Short-Long A-arm front suspension, as most hard use vehicles do. It has a live axle rear suspension, unlike the Explorer’s fully independent rear suspension. The Ford’s independent suspension is better than the live axle on rough and washboard roads. However, the legendary Jeep reputation has been built on live rear axles.

The Heavy Service package includes 17-inch aluminum wheels and S-speed rated tires. The S-speed rating of 112 mph exactly matches the electronic limited top speed of 112 mph.

Steel wheels are not available on any trim level of Grand Cherokee. The cast aluminum wheels meet Jeep durability standards. The special service package Tahoe 4x4 and the special service package Explorer 4x4 also use aluminum wheels. Recent issues with cracked wheels in police use on other vehicles have involved steel wheels, not aluminum ones.

The Heavy Service package includes a 6-inch A-pillar spotlight, wig-wag headlights and 12V power outlets. The custom-made center console is standard. The Heavy Service package also includes an eight-way power adjustable driver’s seat. The Heavy Service package Grand Cherokee has a 160-amp alternator, which is exactly the same alternator output as the police package Charger. The Explorer has a 130-amp alternator.

Unique Upfitting

For this PFM “project vehicle,” we used Whelen emergency gear donated by Coatar & Associates, the Whelen rep in the Midwest. The Grand Cherokee lends itself to some unique emergency light installation.

The fog light receptacles in the lower front fascia, which are empty on the Laredo trim level Grand Cherokee, are perfect for round LEDs. Whelen 4-inch Super LEDs were used. This is exactly the same 4-inch diameter LEDs used in the same location on the Dodge Charger: one side red, one side blue.

We used Whelen Vertex Super LEDs in each corner lens, blue and red in the headlights, and white in the backup lights. The Whelen Avenger LED cluster was mounted in front of the inside rearview mirror, and a pair of Avengers were mounted on the rear headliner for the signal out the liftgate.

On a slicktop vehicle, two other light locations are required to provide 360-degree coverage. One is on the outside rear-view mirror lights, which produce a strong, forward, off-axis signal. The other is on the B-pillar or rear door window lights, which produce a perpendicular warning signal.

Because this is a slicktop vehicle, the Whelen Linz6 LED was mounted to the outside rearview mirrors for the intersection warning, and the same LEDs were mounted to the B-pillars for the side signal.
Finally, the Whelen siren “projector-series” speaker is easily mounted behind the front grille in front of the A/C condenser and radiator.

Driving Impressions

The 3.7L V-6 engine turned out to be OK for all but the most aggressive police work. In urban and suburban driving the V-6 did just fine. To somewhat push that point, during an afternoon of suburban patrol we hauled 480 pounds in the rear cargo area. It didn’t seem to have much effect on any aspect of driving or handling.

The 210-hp V-6 was also perfectly acceptable during county patrol where more time is spent cruising than accelerating. And when we needed to get across the county for a call for service 20 minutes away, the Grand Cherokee did 112 mph without much effort.

No one would realistically use the V-6 Grand Cherokee for traffic enforcement, but we did exactly that. We used the Jeep to enforce reduced speed limits in an interstate “work zone.” This stationary patrol gave us the best chance at catching 30-plus and 40-plus speeders, because all we had to do was drop the Grand Cherokee into Drive and go. The V-6 Jeep got to overtake speeds of 100 mph OK. No one tried to flee and we gave the ticket book a workout.

The 3.7L Grand Cherokee is not a 5.7L Charger. On the other hand, many aspects of traffic enforcement involve a lot of idling. At idle, the 3.7L V-6 uses 20% less fuel than a 4.6L or 4.7L V-8, and 35% less fuel than a 5.7L V-8. The 3.7L V-6 has fuel economy ratings of 16 mpg city, 24 mpg highway. In comparison, the Explorer’s 4.0L V-6 has a rating of 13 mpg/19 mpg.

During traffic enforcement (long periods of idling, followed by wide-open throttle acceleration) and both urban and suburban administrative-type driving, we averaged 16.7 mpg. During rural patrol and highway driving we averaged 18.5 mpg. Overall, in 1,600 miles of mixed driving, the 3.7L V-6 Grand Cherokee averaged 17.4 mpg.

British cops in the Midlands of England and in the Highlands of Scotland patrol in Land Rovers, the world’s premium SUV. So why shouldn’t American cops patrol the rural United States in the Grand Cherokee? This is clearly the most prestigious name in domestic SUVs.

Published in Police Fleet Manager, Sep/Oct 2009

Rating : 9.7


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