I have a 2002 35db 22k workhorse. Make sure the brake recall was done and you should be good to go. I'm sure its Workhorse 8.1 and Allison was a good combination.
Bought mine used. Tiffin makes a very nice coach
Just as a FYI if you need to fix anything. This is what I've done to the coach and approx prices.
Leveling jacks - 1000
Fluids - Transmission, Coolant, oil, tire rotations - 700
New flooring and Carpeting - Did myself 500
New Starter - 500
Exhaust manifold bolts are also an issue, but mine were already replace.
Good luck you'll enjoy your tiffin