The rear shocks are the only auto leveling part so they need air lines to raise the height when you hook up a trailer or carry a heater load inside the rig. The front doesn’t have auto leveling so no air is needed. The front uses electronic signals to tell the shocks how soft or firm to be based on input from several sensors throughout the rig.
Z82 includes wiring for trailer connectors and possibly an electric brake controller among other things.
Z82 includes wiring for trailer connectors and possibly an electric brake controller among other things.