I don't have a truck data book.
When I had new main leaves made for my 3/4 ton at an old school local spring shop, the guy had mentioned to me that the spring packs were the same for 1/2 and 3/4 after looking up the specs.
The Chevrolet Master Parts Catalog also lists the same part number for '47 to '55 1/2 and 3/4 ton (except D-D) for front springs. I've also compared my 3600 springs with ones on a 1/2 ton parts frame that I have. That is how I got my information.
