I saw a youtube video that claims Ram has about 20 (or more) different front springs that are used for 2500 & 3500 trucks. From 4x4, to 2x4, different bed lengths and cab configurations. Seems like Ram does alot of research to ensure each truck has the correct fromt springs for a smooth ride. I have noticed that on rough roads/surfaces though there is alot of travel. Seems RAM stock springs work best on smooth highways. If you add a plow or something on the front, tho, it seems you would need a different spring. If you modify, you need a new spring and if you regularly ride rough roads, you would need an upgrade.