Gdetrailer,
Thanks for your information. I thought the 'training tool' would allow a change to the psi as well. And your note that an owner cannot lower the psi makes sense as I believe they are trying to reduce under-inflation related accidents (Ford Explorer / Firestone finger pointing when owners did not maintain proper pressure).
The only remaining options I can think of (without changing wheels) would be to pursue a tire that rides a little softer. I know my Cooper Discovery tires rode more comfortably than my Michelin's, however they were also less firm when towing and did not wear as well.
For my own purposes I am able to run closer to 50psi on my F-150 (max payload option with LT tires) without triggering the TPMS and the ride is fine. I inflate up to 65 when towing per the door sticker which shows the psi required when loaded. As a reference the Michelin chart shows 65psi supporting over 5k on the axle so that seems right on since my rear axle is good for 4850 (again, this is for the max payload option).
Green728, let us know if you are able to come up with something that helps you out.
Good luck,
Stu