<P> In 2001, DaimlerChrysler commissioned development of a TJ successor under the "JK" program code for the third generation Jeep Wrangler . Design work began almost instantly in 2001, with Mark Moushegian winning an internal design competition against Dan Zimmerman (later responsible for 2005 Jeep Hurricane Concept) by the second quarter of 2003 . In January 2004, the JK design was frozen at 31 months ahead of production and work began on a conceptual preview . </P> <P> On November 16, 2004, Jeep released 2 CAD renders of a Jeep pickup . On December 5, 2004, the 2005 Jeep Gladiator Concept was unveiled ahead of its January 2005 Detroit Auto Show debut, previewing many of the design elements on the incoming JK . The Wrangler JK was introduced at the 2006 North American International Auto Show with past Chrysler group CEO Tom LaSorda driving one up some steps and through a plate glass window, just as Robert Lutz had done at the show in January 1992 with the Grand Cherokee . </P> <P> The 2007 model year brought a complete redesign of the Jeep Wrangler, and also a four - door model . The TJ chassis was replaced by an all new JK platform . This next - generation Wrangler was noticeably wider than the previous model, with a 3.4 - inch (86 mm) wider track; and though the two - door model has a 2 - inch (51 mm) longer wheelbase, it is actually 2.5 inches (64 mm) shorter in overall length than the TJ, allowing for a 44.3 ° approach angle and a 40.4 ° departure angle . With a larger factory available tire size of 32 inches, the breakover angle on the Rubicon is increased from 22.6 ° to 25.4 ° . The four - door Unlimited model has an over 20 - inch (510 mm) longer wheelbase at 116 in (2,950 mm) to offer much improved rear seating room, but is nevertheless only 2.4 - inch (61 mm) longer than the 2006 TJ Unlimited . </P> <P> The JK was first available for purchase with the 2007 model year, beginning in August 2006 . </P>

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