It is quite common for the RV chassis to be the prior year to the RV assembly - but 2 years I hadn't seen before... I assume it is titled as a 2006 RV.
Not sure what to suggest other than talking to the dealer...
What would you want them to do?
I had a 2000 Infinity (30ft) - underpowered isn't a word that came to mind - it certainly held its own - if I was willing to pay the gas bill.
Not yet retired...
Florida (Michigan transplant)
2014 Hurricane 32A
2000 Infinity (previous)