I've heard other people say "If you have to worry about mileage you don't belong in a motor home"...food for thought...IMHO, of course
I've heard other people make that same comment and I think to myself they are very stupid for verbalizing that. Just because someone asks a MPG question doesn't mean they are "worried". Further, everyone should know exactly what economy their RV returns as a variation might mean a problem is brewing.
Ah, quite true but the OP's question seems to reflect the notion to buy rather than compare performance history...IMHO, of course
2004 Cross Country Coachmen
2001 Wrangler behind
JUST HAVIN' FUN!!!
In a 34' coach with the Cummins ISB and a 6 spd trans you should see between 9.5 and 10.5 at between 60-65 mph. I had a '07 Newmar Ventana at a weight of approx 25k lbs and that's what I saw as an average. Use econ mode everywhere except in the mountains and that will help.
2007 Monaco Dynasty Emperor IV
2013 Jeep Wrangler Rubicon