BiIG DAY!
Thanks, DT75FLH. And thanks for the reflective quants. At some point I'll probably paint the entire rig again and your experience provides real world confirmation of some of the research I've done.
So today was one of those milestone days. I actually backed my truck into the shop, lowered the camper onto the subframe, and drove away!!!!! It didn't fall off. It didn't make funny noises, or wobble back and forth, crack, etc.
Granted, this was not an off road test. I just needed to transport the camper from my brother's shop to the paint shop, and the most practical way to do that was on the subframe built to carry it. Adding some weight to my truck really smoothed out the ride (I'd only tried that before I removed the original service body when I put a couple of tons of sand on it). And I was extremely pleased to see the spring mounts do their job when driving through some very deep gutters. The cab and body go their own way, but there's no sway or rebound. I'm still about 2,300lbs lighter than I'll be fully loaded (875lbs of water, 480lbs of batteries, 410lbs of roof crap, plus another 600lbs of food, luggage, etc.) but almost all of that will be under the floor and in front of the axles.
And it was finally good to see the rig's final dimensions in real life:
The roof components should be done at the powder coat shop tomorrow, and the camper's coating will be cured enough by Monday to drive it back to the shop. Then we can put it all back together, pop in the windows and doors, and trim out the inside. I just may get to try this thing out in Southern Utah before the ground freezes!