Try looking up the 2017 28RLSWE on Keystone's website. It "may" be that they produced them on the cusp of the model year changeover and all the data is listed in the 2017 year info rather than in the 2018 info. There is a 28RLSWE listed for 2017.
https://www.keystonerv.com/travel-tr...alf-ton/specs/