I removed the rear tire TPMS sensors to let the pressure down from 80 to 60 since I'm back from my trip and noted the right rear stem was leaking. I put the TPMS sensor back on after reducing the pressure and stopped by my tire store. It seems the schrader valve in the stem was just loose. Tightened and problem solved.
2006 GMC 2500HD CCSB 4x4 Duramax/Allison, Titan 52 gallon fuel tank, Prodigy Controller, B&W Companion Hitch
2010 Jayco Designer 35RLTS, Cummins/Onan RV QG 5500 EVAP, Progressive Industries EMS-PT50C, TST Systems 507 TPMS, RV Flex Armor Roof