The 515 lbs. is the empty TW, add the propane and battery and +++, your actual will be quick over 750 lbs.
Sorry the GVWR of the truck is a bit low compared with other truck manufactures. But you will be fine if you add things up.
2014 Ram 1500 CrewCab 4x4 5.7 Hemi 3.92 Rear and Air Lift 1000
2005 Jayco Jay Feather LGT - 29Y GVWR-6500 lbs.
Pro Series 1200 lbs. WDH with Double Sway Bar.
Champion 3100/2800 watt Inverter/Generator-Onboard Solar Power
ALJO 'Forever Young @ Heart' provide on their travels Music Entertainment to Senior Care Homes