How to convert a 72 c30 to 4wd?

[SS Tim]

There are several ways to do it. There are even two period companies that did conversion kits, NAPCO and Marmon-Herrington. However these were very much vocational trucks and not highway use pet trucks so many are today. Additionaly the parts are hard to find and expensive.

Most people seem to gravitate toward duplicating a K20 setup but the Dana 44 is really too light for anyone "needing" a 1-ton. However that does give you a pattern and some factory parts to work with. Adding a Dana 60 axle would give you the strength and disc brakes the period trucks did not. Yep, a true period NAPCO for example had drum brakes on a closed knuckle axle developed from the Eaton H052 with constant velocity axle joints.
Finally a K20 frame is much lighter than a C30 or C20 longhorn frame. So if you intend on doing anything you need a K30 class truck for make sure the frame is up to it. There have been a number of posts on the subject and a search should yield many links to read through. You can even go to my profile page.