Originally Posted by MY47
Has anyone ever heard of the 5.14:1 axle coming stock in a 3/4 ton??

It is not shown as an option in the Specifications Manual.

1947 Truck Serial Number locations and decoding.

What is your Vehicle Serial Number?
What is your Engine Serial Number?
What is your Rear Axle Serial Number?

Do you have a 125.5" wheelbase?

1947 Chevrolet Truck Rear Axles

I looks like the 3600 and 3800 rear axle housings were the same. It would be an easy swap/option to use the 3800 gears.