Thanks for the answers. We are not new to RV'ing having made several trips to Wyoming to visit our daughter's family, to Florida to follow our son's college baseball team and the East to visit our son and his wife. I am now retired and my wife retires next summer. We are planning to upgrade from out 28' TT to a fifth wheel and travel our beautiful country(we haven't ruled out a Class C). I am well aware of the advantages of a diesel but the big disadvantage is the upfront cost (and I get an employee discount). As one RV sales person told us, "Do your homework." She was speaking of RV's but I have the opportunity to do my homework on trucks, so I am.