History of the 2007-2018 Jeep Wrangler JK, The SUV That Brought Off-Roading To The Masses (And The Mall)

• July 26, 2022
• Story By
  Benjamin Hunting

The Jeep Wrangler's history can be seen as a slow march towards its current status as a hardcore off-road SUV that doubles as a surprisingly livable as a daily driver. From its 1980s roots as the YJ through its modernization as the TJ in the 1990s, Jeep has worked hard to add comfort and features to the Wrangler that soften its attitude on pavement without losing any of its edge when it's time to hit the trail.

The apex of the Wrangler's crossover appeal occurred with the release of the JK generation for the 2007 model year. While the its TJ predecessor had been saddled with the requirement that it use the same frame as the YJ, the JK's higher development budget allowed for a brand new platform that went through six years of design and testing before hitting showrooms.

The end result? Thanks to the JK, the Wrangler became a sensation, transforming into a sales juggernaut that further cemented its status as the Jeep brand's crown jewel. Looking back, however, it's possible to divide the JK into two distinct eras, with early models presenting growing pains that have made them less desirable on the secondhand market.

Bigger And Better

A substantial part of the Jeep Wrangler JK's evolution was the decision to push out its proportions in nearly every dimension. Thanks to its new chassis, the two-door version of the JK gained a couple of inches of wheelbase as well as a wider track, while the stretched-out 'LJ' was transformed into a four-door model that retained the Unlimited name. For the first time, the Wrangler had something to offer off-road fans who needed the extra interior space and cargo room for family duty (plus a set of child seat-friendly access points at the back), and this played no small role in expanding the vehicle's appeal to the masses.

Although Jeep substantially improved interior room and on-road stability with the JK's longer wheelbase and wider stance, the brand's engineers were careful not to overly lengthen the Wrangler's body, helping it stay competitive with the TJ in terms of approach and breakover angles. Still, the additional bulk of the JK is noticeable on tighter trails, especially departure angles which saw a near 10-degree difference between the two, leading many owners to turn to larger tires and lift kits in order to get back to par.

In terms of suspension, the Wrangler JK retained the TJ's coil spring setup in the front and included coil springs at the rear, but top-tier Rubicon models gained electronically-locking Dana 44 axles at both ends. Four-wheel drive systems included a  part-time option for most trims outside of the Rubicon, which came with the automaker's 'Rock-Trac' system that featured an ultra-low crawler gear.

Bad Engine, Good Engine

Under the hood, the initial Jeep offering was disappointing. Gone was the unkillable 4.0L inline six (the vehicle's final link to its AMC heritage), and in its place was a 3.8L V6 that gained the derogatory nickname of the 'minivan motor' due to it being shared with Dodge and Chrysler's people movers. The new V6 was in fact the only available engine to be had with the Wrangler JK, as the previous four-cylinder option found in the TJ had been wiped off the order sheet.

Although the 3.8L was rated at 202 hp and 237 lb-ft of torque—marginal on-paper improvements over the 4.0—in the real world it wasn't capable of adequately motivating the bigger JK with the same authority as the engine it replaced. This was true even when matched with its standard six-speed manual gearbox, and its four-speed automatic limited the Wrangler to a snail's pace. Off-road performance suffered as climbing hills or pulling out of muddy pits often proved beyond the V6's capabilities, and it was also known for burning oil.

When the engine's replacement—the 3.6L Pentastar V6—appeared for 2012, it was a revelation. With 285 hp and 260 lb-ft of torque on tap, the entire driving experience of the Wrangler was transformed, in all conditions and on all surfaces (and a five-speed automatic transmission replacing the older four-speed was also a bonus). It also happened to be more fuel efficient than the weaker motor, giving the JK further appeal to those who planned to drive it to work on Monday mornings.

Aim For 2012 Or Higher

It's here that the internal dividing line between JKs is positioned, with 3.8L models poorly regarded among enthusiasts and priced substantially lower on the used market.

It's not just a weak motor that makes early JKs somewhat of a pariah among brand fans. Although the model boasted a nicer interior, and better amenities than the TJ, there were teething problems throughout the first few years of its production. In particular, electrical systems developed a reputation for being unreliable.

The year before Jeep went with the Pentastar in 2012, it also made substantial improvements to other areas of the JK. Although exterior styling was largely left alone, cabin materials, colors, and design, infotainment, sound insulation, and the availability of a body-color hardtop improved the Jeep's comfort factor.

Peak Wrangler?

The JK might have initially stumbled out of the gate in terms of reliability and drivetrain, but that didn't seem to matter to Wrangler fans jazzed by the appearance of the four-door Unlimited. A strong seller every single year of production (which ended after 2018), the JK lit a spark in Jeep showrooms that has yet to fizzle, and lead directly to the continued popularity of its JL replacement.

It's no stretch to say that Pentastar-equipped JK Wranglers represent the high point for Jeep in combining off-road capability with day-to-day convenience, particularly for those who need the Unlimited's four-door versatility. Nearly as good as the current model, but substantially cheaper, it's well worth paying more for the better engine and avoiding the vehicle's original V6 doldrums.