If you have room , you could consider an LT 265/75R16 load range E tire .
They have a 3415 # sidewall rating at 80 psi .
On the 15 % tougher LT rating scale . Rated for 106 mph .
You can choose from many brands .
I just paid $ 789 to Costco minus a $ 60 rebate for 4 Michelin highway , mounted . LTX MS2 hwy all season
Around here about 40 - 60 % of the 1996 to 2005 vintage GM and Dodge pickups are running this tire on the factory 6.5 " wide wheel without mishap .
An RV wheel is only 6 inch wide but the advantage of using an LT tire is more important .
Plus that 265/75 size is very widely available from every manufacturer at reasonable prices due to it being a high volume size .
LT265/LRE Tire weight is 47 # , diameter is 31.7 " , section width is 10.5 "
An ST235/80r16 is 30.8 " diameter , weighs 37 # , has a section width of 9.3" , but is placarded at 3620 # on the 15 % weaker ST rating scale .
Side by side the ST tire is wimpy , wimpy ...........
GM and Dodge have shipped a couple of million pickups with a 245/75R16 tire on a 6.5" width wheel .
Out west most customers replace that wimpy tire with the 265/75R16 size .