More "techie stuff" on this rig.
With 29,000 lb loaded, three axles and 17.5" tires are mandatory.
The only other option would be going with the 12 or 15K low profile Dexter but that would have introduced other challenges.
The ET Jr. hitch used to pull this rig is rated at 12,500 lb max vertical tongue weight,
and when hitched up it inflates (automatically) to 55 psi, 100 psi being the max, it's an air hitch. That calculates to 6,875 lb on the hitch pin. Subtracting this from 29,000 that leaves 22,125 to be distributed between the three axles and six tires. The axles are 8,000 lb each Dexters.
The suspension used with the axles is made by Ridewell.
It's an air suspension system,
and SpaceCraft is quite familiar how to adapt it to their trailers and frames. I don't think you are very likely to see it on any "Lippert framed rigs".
Each tire needs to carry almost 3,700 pounds which would max out your typical 16 inch G rated tire, hence six 17.5 inch H rated tires.
The rims are Alcoa aluminum rims, obviously these are larger than the 16 inch rims, but it turns out that there is a minimal difference in the diameter (and therefore height) between 17.5 inch tires vs. the 16 inch tires.
The biggest difference is their load capacity,
4,805 lb each meaning that at gross weight there is 1,100 pounds of margin on each tire. It is my understanding that having any margin (at gross) on the tires in any Lippert framed rigs from many manufacturers falls into the category of "wishful thinking".
Anything that is " suspended" and rolling "occasionally" needs to be stopped. Again that falls often into the category of "wishful thinking". On this rig six 8,000 lb disk brakes with ABS.
No I'm not kidding.
You can see the hydraulic line coming in at the top and the ABS ring sensor just below it. You might protest, "but Master, my Tekonsha salesman has never heard about it". "Ah, but my young padawan, you must open your mind to other possibilities, beyond Lippert, Thor and Tekonsha".
"For the good Masters at ActuLink make an electric over hydraulic actuator which also incorporates an ABS interrupter."
"May the braking force be with you"
Incidentally 8,000 lb Dexter disk hydraulic brakes are in another class in comparison to electrics or even Kodiak disks.
Note there there is another hydraulic line coming out of the bottom of the caliper, it goes the outer part of the caliper. In typical disk brakes the caliper will have two pistons on one side only and the brake pads on the other side are held stationary. Dexter uses "dual caliper", it has 4 pistons (two on each side) squeezing the pads from both sides and therefore being able to exert double the hydraulic force.
There are few more things left on the "techie tour" but that's enough for tonight.