IIRC, you could order a 3/4 ton pickup with the following gear ratios starting sometime in the sixties.
The ratios are:
4.55
4.11
3.90
Most trucks were 4.55's, but on the automatics, they generally did 4.11's. 3.90's were available by request, IINM.
There were aftermarket kits available with 3.73 gears, but I do not know who made them.
