Jeep Wrangler Unlimited 2007 Review

Overall rating: 3.5/5.0
Engine/Drivetrain/Chassis: 3.5/5.0
Price, Packaging and Practicality: 4.0/5.0
Safety: 3.0/5.0
Behind the wheel: 3.5/5.0
X-factor: 4.0/5.0

OVERVIEW
Think Jeep and chances are the vehicle you'll picture will be a Wrangler. Indeed, in terms of being anointed the iconic 4x4, the military-styled open two-door is rivalled only by Land Rover's similarly-pedigreed original, now dubbed Defender.

In fact, Jeep has become such a generic term for a 4x4 that nowadays every time the DaimlerChrysler division displays the word, it follows it with a registered trademark symbol -- lest it lose its 'brand' status. It hasn't quite become a verb yet (like Hoover or Google) but it's made it into other languages, including Mandarin, as a noun...

Australia has a strong relationship with Wrangler -- we're the single largest market for the model range outside of North America. To suggest Jeep (and Chrysler's) local fortunes are therefore inextricably linked with the success of the new JK Series Wranglers is a little like saying Ralph Fiennes now lists Qantas as his favourite airline. It's a given...

Jeep's overall success is no less linked to the continued and expanded success of the model. That's why so much effort has been expended in designing and bringing the new model to market. It might look the same as previous generations at first glance (and stay true to their ladder-framed, live-axle origins) but the new Wrangler is all-new.

Indeed, already a runaway success in the USA, it boasts an all-new platform which is larger, delivers more interior space, more safety features, better on and off-road performance as well as new, more efficient powertrains. It also makes one big leap into the 21st Century -- it's now available in a family-friendly four-door.

The four-door gets the model designation 'Unlimited'... And before the wags get too carried away, no, Jeep will NOT offer a Wrangler Unlimited Limited.

The Unlimited Sport is the base model and kicks off as a soft-top with its all-new 3.8-litre V6 petrol engine and six-speed manual gearbox at $34,990. Included in the Sport's standard specification is Electronic Stability Program (ESP), Electronic Roll Mitigation (ERM), four-wheel-disc brakes with Anti-lock Braking System (ABS), four-wheel brake traction control (4BTC), Sentry Key Theft Deterrent System, driver and front passenger multi-stage front airbags, cruise control, fog lamps, power locks with keyless entry, power front windows, soft top, 16-inch alloy wheels, skid plates for transfer case and fuel tank, driver-seat height adjuster, rear folding seat, aircon, floor console and locking glovebox, compass and temperature gauge, 12-volt auxiliary power outlet, tilt steering wheel, single-disc audio system with MP3 input and six speakers and lap-sash belts for five.

The traditional Wrangler two-door soft top also kicks off as the Sport, priced from $30,990 with the same petrol/manual drivetrain. This is a scant $1000 increase over the outgoing model which is more than offset by the added standard equipment (see above), let alone the extra accommodation and convenience the new bigger body delivers.

Both Sport models can be optioned up to include Jeep's new 2.8-litre four-cylinder common-rail turbodiesel engine at a premium of $4000. Auto transmissions are offered on both petrol and diesel versions -- the extra cost is $2000. Jeep's pricing structure is nothing if not simple.

Two higher trim levels of Wranglers will be offered -- again in both two and four-door versions.

The next level up from Sport is the Renegade -- a $2000 premium ($2500 on the Unlimited) that adds adds around $4000 worth of value, claims Jeep.  This level includes a dual top (The Sport's 'Sunrider' soft-top plus a 'Freedom Top' three-piece modular hard-top), deep tint glass, six-disc CD/DVD player, Infinity premium speakers with subwoofer and tubular side steps.

Above the Renegade, the Rubicon arrives in petrol-only as Jeep's off-road 'hero' model boasting seriously uprated running gear to please the rock-crawling brigade.

In addition to standard features on the Sport, the Rubicon model includes stain-resistant seat fabric, electric-disconnecting front sway bar (improves wheel travel), Rock-Trac 4.0:1 deep ratio transfer case, heavy-duty Dana 44 front and rear axles, Tru-lok 4.1:1 locking front and rear differentials, tubular underbody rock rails, 17-inch machined-cast aluminium wheels with upgraded Goodyear Wrangler rubber and interior changes.

The Rubicon level "features all necessary hardware to conquer the world's most extreme trails, right out of the box," says Jeep.

Not surprisingly -- given the level of equipment offered -- the Rubicon upgrade is a hefty $9000 over the standard Sport. Note too, that the Renegade's dual top and uprated audio system are not included in Rubicon's upgrade -- budget on an additional $2500.

MECHANICAL
The Wrangler may be new from the ground up but it is retains much of the architecture of the previous generations.

The chassis is a traditional body-on-ladder frame which also incorporates a welded steel roll cage that acts to protect the occupants in both side and rollover impacts. The frame is all box-section and features wider-set main rails that are hydroformed up front for better crash characteristics. The frame is 100 per cent stiffer in bending and 50 per cent stiffer in torsion than the outgoing TJ series', says Jeep.

The new Wrangler's body is also all-new but retains the Jeep's traditional styling and elements such as separate front fenders, removable doors (with the option of half doors), exposed door hinges and bonnet latches as well as its fold-down windscreen.

Particular attention has been paid to retaining all of the above while also improving NVH. For example the windscreen has a subtle curve in it and the dual corner hinges have been replaced by a single wider centre hinge. These measures improve airflow and therefore reduce wind noise says the carmaker, but does not stop the dedicated Jeepster from dropping the front screen and playing Lara Croft.

Coil-sprung live beam axles are used front and rear. The Wrangler's five-link front suspension features longitudinal location of the axles by leading control arms. A full-width, forged steel front track bar provides better lateral location of the axle and Jeep says lower spring rates were used for the front suspension for a more comfortable ride.

The rear suspension features a similar (but trailing upper control arm) set-up. Unlike its predecessor, however, the JK's control arms are mounted outboard of the chassis rails with the springs inboard to allow for mid-ship mounting of the fuel tank. In addition, rear dampers are splayed (angled inboard at the top) to maintain more consistent dampening between light and full loads, Jeep says. 

Steering is via recirculating ball -- revised for more consistent on-centre feel.

The base petrol engine is an all-new 3.8-litre overhead valve V6 engine with 146kW at 5000rpm and 315Nm 1000rpm lower. The Wrangler is the first rear/four-wheel drive application of this Chrysler Group powerplant. Jeep says the engine is more powerful, lighter, more compact and more fuel efficient than the 4.0-litre inline six it replaces.

Even the thirstiest of the new V6 petrol models, the lower-geared manual Rubicon Unlimited is 0.2lt/100km more economical than the outgoing model's 13lt/100km combined figure. The equivalent new base model Wrangler two-door returns 11.5lt/100km.

A first for a Wrangler -- at least in civilian trim -- is the new range's offer of a diesel engine. The new 2.8-litre four-cylinder common-rail turbodiesel delivers a healthy 130kW at 3800rpm and 400Nm (410 for the manual transmission version) from 2000-2600rpm. Fuel economy figures range from 9.7lt/100km for the Wrangler auto through to 10.0lt/100km for the thirstiest CRD model, the Unlimited manual.

Both engine configurations share Jeep's existing six-speed manual gearbox (which has received a strengthened reverse gear in the update) but different auto boxes are used. The petrol uses a four-speed auto box while the CRDs feature the same five-speed (six-ratio) gearbox as fitted to Jeep's Grand Cherokee and Commander models.

This gearbox features two alternate ratios for second gear. Why? Not sure really... Why not just turn it into a proper six-speeder and be done with it?

The JK Series Jeeps use a good old-fashioned part-time four-wheel-drive system with a manually-operated transfer case. Jeep Wrangler and Wrangler Unlimited Sport and Renegade feature a second-generation Command-Trac transfer case with a 2.72:1 low-range gear ratio.

For increased structural stiffness and sealing, the main case features 18 bolts, versus its predecessor's nine. In addition, flanged front and rear output shafts mated to constant velocity joints on the driveshaft replace sliding yokes, providing better seals and smoother, more efficient operation.

The Rubicon variants call out the big guns, featuring an upgraded Rock-Trac transfer case with a 4.0:1 low-range gear ratio. Also featuring flanged front and rear output shafts mated to constant velocity joints, the unit is engineered exclusively for Jeep for  the Rubicon models.

The Sport and Renegade models feature Brake Lock Differentials (BLDs) which rely on the ESP/ABS low-range and low-speed programming to apportion drive across the axles when wheel slip is detected. The Rubicon again trumps the others featuring Tru-Lock front and rear mechanical locking diffs. These are operated from a dash-mounted switch and also feature a lower 4.10 axle ratio (Sport and Renegade 3.2:1)

For the first time, the Wrangler range gets four-wheel disc brakes -- 302mm vented at the front and 316mm solid rear rotors.

PACKAGING
Even in the case of the two-door Wrangler, the JK series brings with it a hefty increase in interior space. The wheelbase has grown 51mm to 2424mm, while track and overall width are up 87 and 133mm respectively. Overall length of the two-door is now 4223mm -- an increase of 340mm over the TJ series.

The space has benefited passengers and cargo alike. Now offering a rear seat for three and better than token legroom, the Wrangler has almost double its cargo space with the rear seat in place (255 to 490 litres) while the available volume with the rear seats tumbled and folded jumps from 719 to 1600 litres.

In the case of the four-door Unlimited the track and width dimensions are the same (as the two-door) but wheelbase is stretched a further 523mm to 2947 -- longer than the LandCruiser 100 Series (2850mm), Prado (2790mm) or Defender (2794mm).

Overall length (including spare tyre) is now 4751mm -- smack between the Toyos and the Landy.

There's a handy 1310 litres of luggage space behind the second row of the four-door and 2300-litres plus when the seats are folded.

Towing capacities are substantially improved in the new generation too. The Wrangler can now tow 1600kg of braked trailer with the Unlimited listed at 2300kg. Note, however, that the Unlimited's allowable ball weight is well short of the normal 10 per cent of max towed mass at 170kg.

Remember too, that the soft-top or non-structural hardtop options means you'll have to be canny about roof loads. At least both tops are easy to use for the 'fresh-airys' among us. Once you've read the instructions, that is... We managed to break one SunRider soft-top before figuring out what we were doing wrong. Oops.

Jeep makes big claims for its models' respective approach, breakover and departure angles, using phrases like "boulder-friendly", and "best-in-class". The spec sheet places the Wrangler at better than 36 degrees for approach, 23 degrees for breakover and almost 30 degrees on departure, with the Rubicon off-road oriented model a degree or two better in every measurement thanks largely to taller tyres.

The Unlimited matches the front and back measures but, thanks to its longer wheelbase, rampover is reduced to around 19 degrees -- around the same as Toyota claims for Prado. Again the Rubicon variant improves a touch on these numbers.

Of course, all of these numbers are pointless if you can't fit the family into your new Wrangler. While we've detailed the improvement in luggage space, we can't stress enough how much the Wrangler has improved in the way it caters for its most important payload -- you and yours.

Up front there are new, quite sporty, sculptured bucket seats and the rear bench, while a little short in the cushion (same problem as the Compass, coincidentally), is wide enough to sit three. It'll be a squeeze for three adults but three kids are no problem and two grown ups will swim.

Ergos are substantially improved. Featuring grey or khaki interior tones and cloth, the Wrangler also makes a feature of plenty of body-coloured steel... The door trims for example only cover the 'working' bits of the doors -- the rest is structure itself. Pukka!

The instrument panel gets four gauges which Jeep says delivers a "technical aviation appearance". There are better HVAC controls and four vents, four speakers including dashtop tweeters and a larger locking glovebox.

The centre stack includes the audio system and (once available later in 2007) Wrangler and Jeep's first fully integrated navigation system. The MyGIG system uses a touch screen and integrates all audio, navigation and communication functions as well as offering 20-gigabytes of hard drive to store music, images and data.

Extra storage is provided via a lockable centre console as well as a shallow under-floor bin in the luggage area.

SAFETY
The JK Wrangler and Unlimited have taken a step up in safety -- both active and passive.

As noted above, the vehicles structure has been re-engineered to include crash structure front and rear. The roll cage is integral to this structure and driver and front passenger multi-stage front airbags are standard. Supplemental side air bags, housed within the outboard side of each front seat are optional on the Sport and Rubicon ($600) but not listed on the Renegade.

In terms of active safety, all Wranglers get Electronic Stability Program (ESP), Electronic Roll Mitigation (ERM), four-wheel-disc brakes with Anti-lock Braking System (ABS) and four-wheel brake traction control (4BTC).

The ESP provides three modes (on, off and partial) to suit is off-road orientation. The partial mode works especially well on fast dirt roads allowing the sort of 'fun' driving characteristics Wrangler buyers have traditionally looked for with a safety net that most will appreciate.

The ABS system too has an off-road calibration that operates when low range is selected or speeds fall below 15km/h. It allows greater brake force to be applied and longer locking applications to 'cut' through loose gravel.

COMPETITORS
It wasn't that long ago the Wrangler was in a class of its own. And it wasn't first class... Average on-road dynamics and even less impressive NVH and refinement meant it was an enthusiast-only proposition.

How things have changed with the arrival of this model.

True Believers won't be disappointed with the JK -- they can still remove the doors and hardtop thanks to things like removable nylon strap door 'stays' and plug and play wiring. And if they remove the carpets and drain plugs, they can still even hose their Wrangler out!

But, the step up in accommodation, refinement, engine performance (petrol and diesel), amenity (in the case of the four-door) and all-round drivability of the new series means that the Wrangler will now start to feature on family shopping lists.

No more is it up against only the likes of Defender and Landcruiser 70 Series or 4x4 utes. Now the gamut from softroaders to medium SUVs to full-feature 4x4s could potentially be in Wranglers' sights.

And with reasonable equipment levels and competitive pricing it could even encroach on the upper end of the compact SUV marketplace.

Our tip is the Wrangler Unlimited Renegade auto diesel in Jeep Racing Green could be just the thing to have at the foot of the ski-school Poma this winter... On b-i-g wheels and rubber, of course!

And Jeep also plans to import 'industrial' or military versions for an entry into the 4x4 ambulance and other markets. No wonder Toyota's keen to get a new wagon version of the 70 Series to market.

On-road noise levels, ride and handling are all improved. A lot!

Steering is still a touch vague but it's nonetheless a vast improvement on the TJ. You can turn away from the road to talk to your passengers (note we wrote talk, not shout!) and be comfortable you're not going to turn back to the road a fraction of a second later and find yourself on the other side of it!

Brakes too are improved and the petrol and diesel engines are both refined (in 4x4 terms) and plenty powerful enough. If push comes to shove we'd pay the extra for the diesel, but we could also happily live with the petrol. It might be down on torque in the tight stuff but we're guessing that only a fully-laden Unlimited will tax its abilities.

Jeep's launch was in the wilds of western Tasmania and took in a range of sandy terrain as well as the notorious Balfour Track. Though the drought meant the latter was drier than in living memory, its rocky ridges and deep ruts gave us a chance to sample the ground clearance and wheel articulation of the four and two-door Jeeps.

Perhaps the only thing missing from the launch route were some really big hills to test the autos' engine-braking abilities.

Gearing on both the manual and auto variants is well sorted, with the manual's sixth gear delivering quiet (yes, quiet!) cruising on the highway.

Rubicon buyers need to be aware that without that tall sixth (or fifth for that matter), the auto version is revving harder at higher speeds than the Sport or Renegade thanks to its shorter diffs. If you're not a serious offroader, the ability of the standard car will be more than sufficient.

In the sand in 4H it was best to switch to partial ESP as the safety system robbed too much engine power from both the diesel and petrol on the loose surface. This was also the case on the fast dirt roads leading into and out of Savage River. It was on these roads that the corrugations would occasionally catch the live-axle Wrangler out.

This part of Tassie is quite literally wild. If you haven't been there you must. The landscape changes from stark mountain heathland to thick, stunted forest, to sandy ti-tree-lined coastal tracks and back again continually. And the mountain vistas and coastal views are stunning.

It's the type of terrain only a real 4x4 can take you to visit. Now thanks to a raft of improvements, two more doors and decent rear seat, Jeep offers you and your family that 4x4 at an affordable price.

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