I donít really get all that technical about it. For starters, I would gather your 70psi is for max load, I think youíll find that most people donít run their tires at the max.
Unless Iím towing, I typically run my 315ís with a max psi of 65 at 55/60, otherwise itís like rolling on rocks. It depends on terrain, but I usually air down to 35/40 off road or 30/35 for really rough or larger washboard roads, helps smooth things out a ton.
Get yourself a decent quality compressor, the cheap ones usually over heat quickly and take forever. The ARB or Viair units are nice.
Tires with larger sidewall also help, you may be able to upgrade to a 265 on your next set.
A nice set of Bilstein shocks will also help you out, donít let the name mislead you, look at their ďcomfortĒ series.
'03 Ford E350 7.3L Diesel
(de)SMB'd Custom RB-50
Quigley 4X4 w/Deavers & Agile Offroad's R.I.P. package
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