Mr. Roy,
We went from 42 ft. to 45 ft. and I thought it was not going to be much of a difference but it IS different. Not difficult, just different. I have to swing wider in RV parks and keep an eye on the rear wheels. I have found myself closer to a curb than I thought I would be.
Obviously, a 38 ft. would probably have a single rear axle. In tight turns you will want to lift the tag for a tighter turning radius. Our tag does not lift but releases pressure as not to drag the tag axle in tight turns.
Safe travels,
MM.