I installed the Lorenz-Bilstein B-5100 suspension kit on my '03, 3500 SRW a couple of years ago & love it. Before, if i hit the speedbumps in my neighborhood at anything over 10 mph. , the front suspension would bottom out. I've gone over the same bumps at 20 mph with no sign of bottoming out. Much smoother ride in bumpy conditions, dirt roads, etc. I had more trouble installing the rear spring pack than anything else. Did the front myself & I'm far from being a mechanic. Had to get some help with the rear suspension.
All in all, I'm very glad I bought the Lorenz Bilstein B-5100 system. Works very well. Even my Duramax friend who didn't like the ride of the Dodge asked what I had done differently when I took him for a ride down a dirt, washboard road. He LOVES his Chevy!!! Especially the ride.
Joe F.