Recently, my '03, 3500 SRW, @ 59,000 miles needed shocks & I decided to go with the Lorenz Bilstein 5100 System. This system includes new front coil springs that raise the front end by about 1-1/2" & a spring pack that replaces the big lower bar on the rears. It makes the rear spring more progressive instead of feeling like the rear is bottoming out when you hit that big bar (spring).
Before the Lorenz System, you could bottom out the front end, easily. there wasn't much room between the axle & the bump stops. Now, you can hit speedbumps & the shock is absorbed nicely by the longer springs & shocks. I've hit them at about 25+ mph. & the system absorbs the bump well.
If you want a bit more than just shocks, the Lorenz System may be something to consider.
Joe F. (Buffalo)