Why do you think a 31 foot gas motorhome will have issues in the mountains, my 32 foot gas Bounder does good and I tow 6000 lbs behind my RV, granted its not a rocket in the mountains but it does get the job done while maintaining at least 45 mph.
Also what chassis do you have, if its the Ford F-53 like mine get the 5 Star tuning program uploaded and it will shift better and have better torque in the lower RPM's, also sound proof the doghouse and under the floors in front driving area and it will be much quieter than stock..
Gas motorhomes are cheaper to service and repair...
