If you’ve kept an eye on BDS’s kit listings over the year, our kits have been consistent to 1”/2”/2.5”/4”/6”/8” lift sizes on 2005 and up models. Recently, in an effort to provide a more accurate “net" lift height achieved on the 2020+ trucks, we have updated the kit listings to reflect the true net lift heights of 1”/2”/3”/5”/7”/9” for new models.
This is not a reflection of different springs/components, but rather factoring in the 2020+ Super Duty trucks comes from the factory about 1" lower than the 2017-2019 trucks so our springs will net roughly 1" more lift than previously listed, even though the final ride height is the same on al 17-23 trucks. For that reason the 6" lift height is now listed as a 7" lift on the newer trucks even though they use the same springs.