Machine description: Isuzu 6 Cylinder 7.8 L Diesel Engine, 2008 US EPA Label, Allison Automatic Transmission, 36580 lb GVWR, 11R22.5 Front Tires, 445/50R22.5 Super Singles Rear Tires, Spring Suspension, 152 in Wheelbase, ... more info about the 2009 GMC T8500.