Among Jeep enthusiasts, few models carry the kind of reverence reserved for the 2004–2006 Jeep Wrangler Unlimited LJ. Often referred to as the “Long Jeep,” the LJ represents a perfect balance of classic Jeep design and enhanced capability. It retains everything enthusiasts loved about the TJ (compact dimensions, the legendary 4.0L inline-six, and analog simplicity) while adding meaningful improvements that make it both more practical and more capable on the trail.
Produced for only three model years, the LJ has become something of a cult classic. Today, clean examples command premium prices and are frequently sought after by builders who want the ideal foundation for a serious trail rig.
But even legends can be improved, and that’s where RPM Steering & Suspension’s LJ Upgrades comes in.
Why the Jeep LJ Earned Its Legendary Status
Before diving into the suspension upgrade, it’s worth revisiting why Jeep enthusiasts consider the LJ one of the best Wranglers ever built.
More Space Without Losing the Classic Wrangler Feel - The LJ is 15 inches longer overall than the standard TJ, translating to a 10-inch longer wheelbase and dramatically more usable cargo space. That extra room behind the rear seat makes the LJ far more practical for camping trips, overlanding setups, or hauling gear to the trail. Unlike modern four-door Wranglers, however, the LJ retains the classic 2-door Wrangler proportions, preserving the nimble feel that TJ owners love.
Improved Stability on the Trail - The longer wheelbase isn’t just about cargo space, it also delivers significant advantages in off-road stability. On steep climbs, ledges, and technical rock obstacles, the LJ’s additional wheelbase helps reduce the “bucking” effect common with shorter rigs. The result is more controlled traction and smoother obstacle transitions, making the LJ a favorite among serious rock crawlers.
The “Holy Grail” Drivetrain - Many LJs were equipped with what enthusiasts consider the ultimate TJ-era drivetrain combination:
- The 4.0L inline-six engine, widely respected for its durability and torque
- Either the 4-speed automatic or 6-speed manual transmission
- Optional Dana 44 rear axle
This combination provides a strong and reliable foundation for builds that range from mild trail rigs to full-blown rock crawlers.
Rarity and Collector Value - Because the LJ was only produced from 2004 to 2006, relatively few were built compared to other Wrangler generations. As a result, the LJ has achieved near-mythical status in the Jeep community, with values steadily climbing as demand continues to grow.
Elevating the LJ Platform with RPM’s Long Arm System
While the LJ already starts with an excellent foundation, all factory suspension geometry has limitations when you begin pushing the vehicle harder on the trail. RPM Steering set out to completely rethink the LJ suspension layout, creating a system that maximizes articulation, stability, and durability while maintaining clean, functional packaging.
The result is the RPM LJ 3-Link Front / Double-Triangulated 4-Link Rear Long Arm Upgrade.
True Double-Triangulated Rear Suspension
Unlike factory link geometry (or even many aftermarket kits) this configuration eliminates the need for a rear track bar while dramatically reducing rear steer under articulation. The advantages include:
- More predictable handling on technical terrain
- Improved articulation without binding
- Reduced lateral axle movement
- Better traction when climbing or descending obstacles
For Jeep builders focused on serious off-road performance, a properly designed double-triangulated system is widely considered the gold standard for rear suspension geometry.
In addition to these performance improvements, RPM designed this system with serious trail abuse in mind, combining premium materials with thoughtful engineering throughout the kit, including:
- Weld-in side brackets with integrated front link mounts
- Third link mount for the front axle
- Bolt-in rear crossmember supporting the double-triangulated rear geometry
- Truss-top 4-link mounts (rear truss not included)
- Axle-side lower control arm mounts
- Bolt-in transmission mount crossmember
- 1/4" laser-cut skid plate with CNC-smoothed bottom
- 7075-T6 aluminum control arms with RockJock joints
- All required Grade 8 / 10.9 hardware
- RPM offers multiple rear stretch configurations to accommodate different build goals:
- Stock Length
- 4-inch Rear Stretch
- 7-inch Rear Stretch
The 7075-T6 aluminum links are particularly noteworthy. This aerospace-grade aluminum offers an exceptional balance of strength, weight savings, and corrosion resistance, making it ideal for high-performance suspension systems. Paired with RockJock narrow joints, the system delivers smooth articulation while maintaining the strength required for aggressive off-road use.
Smart Design for Real-World Maintenance
One of the standout features of RPM’s system is the removable skid plate design. Many long-arm kits require supporting the transmission when removing the skid plate, complicating routine service. RPM solved this problem by designing a skid plate that can be removed without supporting the transmission, making drivetrain maintenance far easier. For anyone who regularly services their own Jeep (or spends time repairing trail damage) this kind of thoughtful engineering makes a big difference.
Installation Considerations
Because this system is designed for high-performance suspension geometry, installation does require fabrication and modification. Key installation requirements include:
- Welding brackets to the frame and axles
- Installing a rear axle truss (not included)
- Fuel tank relocation for stretch configurations
- Evaporative canister relocation for stretch setups
- Custom exhaust modifications
Additionally, coilover/ORI towers and track bar relocation bracketry is not included in the base kit but are available as an optional add-on. These requirements reflect the fact that this kit is built for serious builders and fabricators who want the best possible suspension performance from their LJ platform.
The Ultimate Suspension for a Legendary Jeep
The Jeep LJ has long been considered one of the most balanced and capable Wrangler platforms ever produced. With its longer wheelbase, legendary drivetrain options, and classic Jeep styling, it remains a favorite among enthusiasts who value both performance and simplicity.
RPM Steering’s 3-Link Front / Double-Triangulated 4-Link Rear Long Arm Upgrade takes that already-exceptional platform and pushes it into a new category of off-road capability.
For LJ owners looking to build the ultimate trail machine, this system delivers the articulation, strength, and suspension geometry needed to tackle the toughest terrain, while preserving everything that made the LJ legendary in the first place.
