Check out the GM Workhorse division's website. Lots of info and pics of the modern version of the chassis under our Airstream motor homes. The new 8.1 liter Vortec engine for those needing more power, 340 ponies 455 ftlbs torque. Four wheel disk anti-lock brakes, Hydra-matic 4L80E auto 4 speed, electronic control with cooler and on and on....
http://www.workhorsecc.com/rvs/p32/satisfaction.asp