transmission i.d.?

[guffey24]

I am looking at buying a used older model truck for my new business venture

transmission is slipping

here are the specs of the Truck

1981 F-150 Ranger, 2wd, 302, 3 speed auto with overdrive maybe

can anybody tell me what tranny that would be?

 

[ghost]

If it is an overdrive it sounds like an AOD.

 

[Ron]

overdrive = aod
non overdrive = c4


all this assuming it is factory of course.
If it has been changed along the way, well its anyones guess