We also own 2006, 8356 Crescendo. Ours is on a Freightliner Chassis with a C7 Cat Diesel 300 hp and Allison 6 sp transmission. We have averaged 8.6 - 10.6 mpg depending on wind, alititude, driving speed, etc.
This is our home as we are full-timers and, after a little remodeling, couldn't be happier. We have had NO problems with anything in this coach and we are thrilled with the customer service we have received from Gulf Stream.
2006 Crescendo 8356DP C-7 Cat, Freightliner Chassis
Suck, squeeze, bang, blow...Down the road we will go