Dodge was the major producer of most of the motor home chassis from early (mid 1960s)on until they went BK the first time in 1980,
The class A motorhome had a special RV chassis on either a 1.5 ton 0r 2.5 ton chassis, the class B and C motor homes were built on a 3/4 ton or 1 ton van chassis, class B did not have a generator included, class C did.
I use to see train cars full of those chassis, all three, on a daily basis being taken into SO CA from back east to the motor home makers in SO CA, lots and lots of them.
Once they went bankrupt the federal government made them stop making those chassis due to Ford and GM lobbyist, same thing on large truck chassis(2 1/2 ton or larger) also