Those are not the only axle ratios involved either. This transmission was used '48 to '67 in 1/2-ton to 2-ton and possibly larger trucks. The probable rear axle ratio list would be pretty long...

3.90
4.11
4.57
5.14
5.43
6.17
7.20

And I'm sure this is not an exhaustive list.

1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more...
It's true. I really don't do anything but browse the Internet looking for trouble...