I note the three tires mentioned
XRV 305/70R22.5 LR-L 7830# @ 120 psi 39.1 OD 12.3 wide
XZA2 Energy 295/80R22.5 LR-H 7830# @ 120 psi 41.2 OD 11.8 wide
XZA2 Energy 315/80R22.5 LR-L 9090# @ 130 psi 42.3 OD 12.5 wide
138.4# weight 7920# @ 115
The above loads are the single (front) load & inflation ratings
You didn't mentioned the actual loads on each corner of your Dutchstar or your GAWR. Also your rims might be pressure or load limited so you need to confirm those numbers too before you make a switch.
I don't know supply or cost figures where you live but normally weight is a good relative measure of tire cost. It might also give an indication of the impact on fuel economy with heavier tire being worse.
Retired Tire Design and Quality Engineer (40 years experience).
Retired Professional race car driver.
Retired Police Driving Instructor.
Member, FMCA Technical Advisory Committee
Delivered Tire Seminar for RV owners & two seminars on Genealogy at FMCA Bowling Green 2009, Madison 2011,
Indy 2012, and Perry & Redmond 2014
I hope to present two seminars on RV Tires & Three on Genealogy at Madison, WI in August 2015
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