Does anyone have any ideas for making the ride better and at the same time lowering the back end about 6"? Was driving around with a 850 lb. steel plate, but this is not the long term solution I want. I was going to rearc the springs, but he two piece drive shaft geometry would be off. Any ideas?

I got a pretty decent ride by removing a couple of leafs and the overload pads on the frame. I then used a set of drop shackles. Ended up with about
4" of drop. 6 would probably require c-notching the frame. Air bags are available to pick the load capacity back up, but we never really needed them. I also notched and gusseted the factory torsion adjustment pockets and removed the front snubbers. Doesn't look as much like a 4x4 now.:)

Which vendor's lowering shackles would you recommend? I'm thinking about lowering my 2006 crewcab 3500 SRW and 2 inches would be about right. I'm thinking the dually and SRW shackles are interchangable. Right?

Bell Tech is the brand we used.:) Don't know about what they fit, and the Bell Tech catalog didn't even cover the 04 at the time.