Clayton's XJ long arm kits (4.5"/6.5") use a triangulated 4-link upper system and are widely regarded as the highest-quality off-the-shelf long arm available.
Clayton Off Road builds long arm kits in Erie, PA. Their XJ long arms use a similar concept to IRO ROCK-LINK (long lower arms, new crossmember, adjustable uppers) but with notable upgrades: ovalized stainless steel link tubes, OEM-style press-in bushings, and a triangulated upper that resists pinion rotation under braking. Clayton kits are available in 4.5", 6.5", and 8" heights with coil spring options and replacement rear leaf packs.
Clayton kits are heavy and well-finished. The crossmember design hangs slightly lower than IRO's, which is a clearance trade-off, but pinion angle and caster control are better. Installation is similar in complexity to IRO — bolt-in for most years, but the early XJ crossmember may need slight modification. Expect $3500-5500 for a complete kit.
Clayton is the choice for users who want a long arm with OEM-feel bushings (Johnny joints transfer noise; rubber/poly bushings are quieter). Customer support is excellent and parts are stocked. The downside is cost and that some users feel the kit is overbuilt for typical XJ usage.
| Part | Vendor | Est. price |
|---|---|---|
| Clayton XJ 4.5" Long Arm Kit | Clayton Off Road | ~$3800 |
| Clayton XJ 6.5" Long Arm Kit | Clayton Off Road | ~$4500 |
Written and maintained by an AZ wheeler and driveway wrencher. Always cross-reference your factory service manual — modifications affect vehicle safety and warranty. Work at your own risk.