The short answer is no, they are not interchangeable. Your truck most likely has an Eaton HO52,HO72 rear axle. Check to see what gear ratio you have, but 4.56 is the fastest As I recall. Look in the 1 ton forum, pinned at the top is A LOT of information about axle swaps for better gears. Most of this info is applicable to 3/4 and 1 tons.
Jon
