Machine description: Isuzu 6 Cylinder 7.8 L Diesel Engine, 2000 US EPA Label, Allison Automatic Transmission, 14600 lb Front Axle, 23000 lb Rears, 37600.0 lb GVWR, 11R22.5, Spring Suspension, 171 in Wheelbase, PTO, Double... more info about the 2007 GMC T8500.