Look at the site I have included and ask your questions there. Brand specific:
http://aspectcambriarvforum.forumotion.com/
Now I believe you should have but and not certain air bag suspension in the rear? You need to determine what pressures you need to have an effect on the ride. 80PSI is max and may not really be needed but if it is you will need a higher rated tire other than the E's probably on it now? Not sure you could even run larger wheels tires on these, maybe with a lift kit?
Go to another scale and re-weigh to see where you really are at weight wise see if they can do individual wheel locations or if by axle only. My 12 aspect 28 is under 13000 or so lightly loaded. If towing a trailer, as noted earlier try to go to 4 down vehicle, adds virtually no tongue weight.
So drop by the aspect site and join in the conversations there. I did post a link to your 1st post but not much happened.