I have not used helper springs or air bags. I do think air bags are the way to go.
Are you using load leveling bar on your trailer and hitch ? If so can the leveling bars be adjusted for extra load.
06 Titan LE,4x4,Steel Leather,Red Alert,Big Tow,Factory Step Rails,Brush Gaurd,Floor Mat,Bed Extender.. Add On's- In Channel Window Vent,Rear Spoiler mounted on RollBak Retractable bed cover... 2 Deg Timing Mod.. AirRaid TBS... NISMO Cold Air Intake.. BullyDog GT III and FlowMaster cat back dual exhaust.. Drilled/slotted rotors and Evolution pads front and rear.. JBA headers, rear sway bar.