I'm piecing my Carli suspension together piece by piece for my 3500 and so far I have the radius arms, radius arm drops, 3" springs, sway bar, and track bar. I know if I use the full progressive leaf spring pack for a better ride, my truck will no longer be a 1 ton truck, are there any air bag kits out there that can be used when hauling a load without the loss of suspension travel when not hauling a load? I've never had airbags and assume they would limit travel.