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Written by Bill Visnic
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Okay, maybe the 2018 Jeep Wrangler could be considered SAE autonomy Level 0.5 after all, the all-new version of Jeep"s icon does offer a couple of automated driver-assist features. If you must. But apart from that concession to contemporary development trends, the new Wrangler is unabashed in its dedication to the analog driving experience: it"s updated, upgraded and more refined, but it"s unquestionably the most elemental new vehicle of 2018. After all, name another all-new model that pridefully comes to market at the dawn of the automated-driving epoch with solid front and rear axles, a windshield that folds down and doors that come off. That"s before you get to ground clearance increased to an almost comical 10.9 in (277 mm), lock- em-on-yer-own front and rear differentials and four-wheel drive. And forget full-blown electric power steering the Wrangler"s just now progressing from recirculating ball to electrohydraulic rack and pinion. There"s only one reason for all this rawness, of course. It was decided the all-new Wrangler couldn"t relent a bit on its go-anywhere legacy. Those ready to embrace the automated-driving future simply need not apply. "Wrangler built its name on off-road (capability)," said chief engineer Brian Leyes. "We weren"t going to compromise on that." New but familiar design Those not steeped in the heritage that traces to the Jeep"s introduction in 1941 won"t instantly identify this new JL-generation Wrangler by its general shape it looks a lot like the previous-generation JK-series Wrangler (introduction 2007) and not all that different from any Wrangler of recent recollection. Know to look for that extra second, though, and the "faster" windshield rake, slightly back-sloped grille and markedly lower beltline and larger side windows might be a giveaway to the new Wrangler"s 9% slicker aerodynamics even if its 0.454 coefficient of drag remains more brick than bullet train. The 2018 Wrangler"s grille is all-new, of course, as is the rest of the sheetmetal (which now is a lot less actual metal) and the grille"s latest interpretation of the 7-slat treatment an utterly non-negotiable styling cue was intended to pay homage to some of the development team"s favorite Wranglers of the past. Maybe not surprisingly, the longest-running Wrangler, the CJ5 (1955-83) comes up in many conversations. "We wanted to put a lot of CJ5 into it," said Mark Allen, head of Jeep design. "The character of the grille is much more CJ5, in my mind." The fenders, now aluminum, are 2 in (50 mm) higher and 33-in (838-mm) tires, available for the first time for a Wrangler, contribute to the actual and perceived higher stance. Wheelbase for the 4-door Wrangler is up by 2.4 in (61 mm) to 118.4 in (3007 mm) and increases by 1.4 in (36 mm) for the two-door to 96.8 in (2459 mm). It all makes for a larger and huskier footprint, although one would need a current JK-series Wrangler nearby to make the upsizing obvious. "We want the vehicles to all look a bit modded" straight out of the factory," asserted Allen. The new Wrangler"s windshield continues its tradition for folding onto the hood if desired and the design team is proud of the decision to retain the feature as well as its execution. For the outgoing Wrangler, dropping the windshield required the removal of 28 bolts and the curved windshield laying on the hood, "looked stupid. Nobody did it," said Allen. Now, thanks to the new "sport bar" in effect, a fully integrated, body-color rollcage that, in front, forms an A-pillar-spanning structural header bar foundation for the windshield one simply removes four bolts and the windshield can be folded down and secured to the hood in less than five minutes, Jeep claims. Why all the bother for a function few owners will ever really employ? As usual, deference to Jeep tradition. "It felt good to keep it," said Allen. The three trims Sport, Rubicon, Sahara can be had in either the 2-door or 4-door configuration. With a new power folding canvas top, an improved-design full soft top that does away with the accursed zippers and a removable composite hardtop, there is a conglomerate of potential body/top configurations. The removable doors are markedly lighter and have been designed to ease the removal process. There is a unique half-door option coming for 2019. Weight abate High-strength steel (HSS), aluminum, composites and even magnesium all get into the 2018 Wrangler weight-loss program that delivered a roughly 200-lb (90.7-kg) reduction for the 4-door and a 140-lb (63.5 kg) cut for the 2-door models, said Dave Bustamante, Model Responsible Jeep Wrangler. The heaviest 2018 Wrangler, the 4-door Rubicon, is listed at 4484 lb (2034 kg). The 2018 Wrangler"s totally new frame is fully boxed, with 80% now formed from high-strength steels. The weight reduction from the new frame alone was nearly 100 lb (45.3 kg), said Bustamante. The are five boxed crossmembers and hydroformed front rails that engineers said better handle loads from the front suspension. The new design and the high ratio of advanced steel enabled an 18% increase in the frame"s overall torsional rigidity. All closure panels, including the hood, now are aluminum, as are the windshield frame and fender flares. The rear swing gate is formed from a cast magnesium inner and aluminum outer skin and is a substantial and tangible-feeling 50% lighter than the outgoing Wrangler"s tailgate. The new frame is anchor for the familiar 5-link suspension at each corner, but chief engineer Leyes said care was taken to keep the upper and lower control arms tucked within the frame a boon for off-roading that combines with a roll center that"s hiked up by 2.5 in (64 mm) and those 33-in tires (Rubicon only) for unparalleled ground clearance and fording capability. "When we redesigned, we were tucking things up," Leyes said. Leyes added that the new Wrangler"s suspension geometry is completely revised and new damper tuning, steering angle, hard points and body mounting combine with a wider track to tighten the turning circle by a little more than 1 ft (305 mm) another significant metric for off-roaders, who value tight turning despite the new Jeep"s lengthened wheelbase. "We"ve been on trips going down the mountain where the previous Wrangler had to do 3-point turns. That"s where it (the 2018 model"s tightened turning circle) really became apparent to me," Leyes said.<br /> Jeep said ride comfort, handling and body roll also are "significantly improved" by the new suspension setup. Automotive Engineering"s off-roading of the 2018 Wrangler on quick-ish desert trains seemed to lend credence to the claim: head-toss was noticeably non-existent and the general state of tuning was one of pleasingly controlled compliance. The Rubicon model gets an electronic front sway bar disconnect to maximize front-wheel articulation for extremely technical trail work. You"d expect industry-leading approach, breakover and departure angles and you"d be correct: the respective measures are 44 deg, 27.8 deg and 37 deg. New powertrain, 48V efficiency boost The 2018 Wrangler has the model"s first-ever turbocharged 4-cylinder engine, an all-aluminum 2.0-L direct-injected unit charged by a twin-scroll turbo with an electronic wastegate. The engine serves up 270 hp and 295 lb ft (400 N m) more torque than the carryover 3.6-L DOHC V6, which becomes the Wrangler"s base engine when the 2.0-L starts availability in the second quarter of 2018. Wait a minute, though: aren"t turbocharged engines and their unpredictable torque "hit" anathema for rock-crawling and tight-trail adventures? "There"s obviously concern about turbo lag," said Leyes. "But the controls associated with this engine are very good. And with the (transmission) crawl ratio we have, you"ll very rarely be in the boost." But he admits hard-core customers may need convincing. "We"ll be careful. I think word will get out that it"s pretty good." But there"s more. The new engine comes standard with a 48V belt-starter generator system called eTorque. It provides mild-hybrid features such as engine start/stop and regenerative braking, but also improves fuel economy with a torque input to "fill in" before the turbocharger is delivering full boost, extend the duration of engine fuel shut-off and enhance transmission shift schemes. The company says eTorque also means the engine and fuel flow may be turned off at idle, or when coasting. Meanwhile, the new Wrangler"s 3.6-L V-6 isn"t exactly carryover: it"s the second generation of FCA"s widely-deployed Pentastar and now develops 285 hp and 260 lb ft (353 N m). It can be backed either by a heavily revised 6-speed manual transmission or a new-to-Wrangler 8-speed automatic, a considerable upgrade over the outgoing model"s 5-speed auto. At the time of the media introduction, FCA wasn"t yet dealing out fuel-economy figures for the 4-cylinder Wrangler, but the V6 model"s numbers have improved to 18 mpg city/23 mpg highway for the automatic and 17 mpg city/23 mpg highway for the 6-speed manual. The outgoing 4-door Wrangler V6/automatic is rated at 16 mpg city/20 mpg highway. In a final "first" for the all-new Wrangler, the Sahara can be specified with an optional Magna-supplied Selec-Trac 2-speed transfer case that features automatic engagement of high-range 4-wheel-drive; 4-wheel-drive high and low ranges still can be selected manually. The set-it-and-forget it system is engaged via the same chunky console lever as the Wrangler"s two other part-time transfer-case choices. Starting in 2018, 4-door variants of the new-generation Wrangler will be available with FCA"s VM Motori-designed 3.0-L EcoDiesel V6, earmarked to develop 260 hp and 442 lb ft (599 N m) of torque, with standard engine stop-start. The 8-speed automatic will be the only transmission hooked to the diesel, which is scheduled to feature several design upgrades. All Wranglers will continue to be built at FCA"s assembly plant in Toledo, Ohio. Refinement not a dirty word Along with the lengthy list of upgrades for the JL-generation Wrangler is a marked improvement in NVH and refinement. It may sound rudimentary, but the new Jeep"s full-length front-door armrests, for example, are a gee-whiz moment, and there"s standard HVAC for the rear-seat occupants and a more comfortable degree of seatback recline. "This is the most refined Wrangler we"ve ever created," Jeep interior design manager Ryan Patrick Joyce flatly said. The dash center finds either a 5-, 7- or 8.4-inch touchscreen, the largest version featuring all the latest functionalities of FCA"s excellent Uconnect interface. The standard driver-information display is a 3.5-in LCD, with a gorgeous optional 7-in version displaying a variety of entertaining and useful information for on- and off-road operation. Pushbutton start is standard and there is a total of five USB ports and depending on model, the grade of materials throughout is significantly upgraded; the upscale Sahara trim, for example, features a hand-wrapped dash and Joyce said all the exposed interior metal is just that genuine metal. There are four standard airbags and the new Wrangler also offers blind-spot warning and rear cross-path detection and a standard rearview camera cleverly packaged on the spare-tire carrier. The new interior may be a mightily more-hospitable place, but traditional concerns still got the final nod. Despite all the new creature comforts and technology enhancements, the 2018 Wrangler continues with fully removable carpet and floor drain plugs to facilitate hose cleaning. Touche" to the forces of autonomy. <br />



Date written: 18-Dec-2017 01:24 EST

More of this article on the SAE International Website

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