Designed for those who already have a Rubicon Express short arm suspension system, the Rubicon long arm upgrade system will allow for an easy upgrade to a Long arm suspension. The Extreme-Duty? long arm suspension system will provide noticeable improvements in your XJ's road handling. Off road, you will se unmatched performance on the most extreme trails. This package includes: a new crossmember and all 4 front Extreme-Duty control arms. Lift height will depend on the system you are upgrading.