The JK Wrangler generation introduced the factory four-door Wrangler Unlimited.
The third-generation Wrangler, known internally as JK, debuted for the 2007 model year and fundamentally expanded the model’s appeal. Alongside the traditional short-wheelbase two-door, Jeep offered a long-wheelbase four-door called the Wrangler Unlimited. It was unveiled at the 2006 New York Auto Show and entered production in August 2006.
The JK Unlimited was not simply a stretched version of the earlier TJ Unlimited. Its wheelbase grew by about 20 inches, compared with the TJ-based Unlimited’s roughly 10-inch extension, creating substantially more rear-seat and cargo space. The four-door model was offered in trims such as X, Sahara, and Rubicon.
A common mix-up is assuming the Unlimited name itself began with JK. The TJ generation had already used that name on a two-door, long-wheelbase model. JK was the generation that made the factory four-door Unlimited a mainstream Wrangler configuration. The later JL generation replaced JK beginning in 2018.