Class A motorhomes with diesel engines use diesel gas, and Class A motorhomes with gas engines use regular gas. Class A motorhomes can be purchased with either a diesel or a gas engine, but the diesel engine is more powerful and better for rugged terrain.
Class A motorhomes are considered the largest motorhomes, with the most interior space and storage, and can fit up to eight people. They are also the most expensive and luxurious motorhomes. Because of their size, Class A motorhomes can't be parked at some National and State Parks because the spaces aren't big enough for them.