Traction bars are a great add-on suspension accessory for a lifted truck. Large diameter tires require some extra torque to get the rubber moving down the highway. Traction bars will keep the rear axle from wrapping (twisting your rear leaf springs) which improves acceleration and traction.
Jackit offers a handful traction bar of options from top brands lift BDS Suspension and Rough Country. Check out the BDS Recoil Traction Bars with a spring loaded design for something really awesome!