Ford and Chevy both have specific specs on how far their chassis may be stretched, and how it is to be done. Ford, if I recall, allows just a little more than GM does, so the very longest ones will be on Ford. Ours is a 31, a little over 32 overall. As the coach is stretched, several things can happen:
1. Turning circle will increase. The E-Series only has about 25-degrees of front wheel "cut" so we have a HUGE turning circle. It has never prevented us from making a turn on a road, except a U-Turn. Takes four lanes and one shoulder to do that.
2. The overall coach may be very close to GVWR. Longer frame and bigger, therefore heavier, body go together.
3. Handling may or may not suffer. The floor plan seems to have more to do with wheelbase than actual weight distribution. That's unfortunate. It's possible for a coach to be over weight on the rear axle while too light on the front axle. Not just hard on tires. Too light a front end will allow the coach to wander on the road. Ford wants AT LEAST 1/3 of loaded weight on the front axle. That's probably skimpy for a long, wide, high motorhome.
Wheelbase affects all this! The newer 31's have a wheelbase around 220". ALWAYS weigh a coach you're considering. Drive it to a CAT Scale, get Front and Rear Weights, then adjust Tire Pressure according to Michelin's RV pressure chart. Then continue your test drive and see if it's better.
EDIT: I see you posted this in Super C. Same factors apply, you just have more weight to work with.
