I just purchased a '72 D100 with a bad \6, someone added a 4spd transmission that I am having trouble identifying. There is no ID plate
on the unit, but it does have a 'belly' pan that drops so you can change the clutch w/o removing the engine. The clutch plate is 11". Is this
some version of an A-833 or some other model? Engine still runs, but the oil pump gear was broken...wonder how long it was driven w/o oil pressure?

Sounds like you may have the "granny low" truck 4-speed. Does the shifter go right into the top of the trans?
Here is a link which may help ID the unit:
http://www.slantsix.org/articles/4-spee ... speed1.htm
DD

Yes it does, great article! Thanks Doc.