It may be, my 2006 Tioga is on a 2005 chassis. On the CCC sheet, below, it lists it as a Tioga Commercial. Work Horse Chassis started in the 2004 model year.
His thinking is that being on a Work Horse Chassis that were made for the commercial market, like School Buses or Ambulances and such. MAY have a larger or more robust cooling system. As you know mine was a Rental as NTORACN's was. We will have to find out what his says.
He is still doing some research.
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