How do I identify the rearend in my bus? 1956 4400. I have a pic of it, but do not know what I am looking at as far as what kind it is and whether it is 2 speed or not. Can you help me identify it?

http://i107.photobucket.com/albums/m290/fclaridge/th_Rearend.jpg


1956 Chevy School Bus Superior Body
In the Stovebolt Gallery