Superviking

Hello ! 2018 S6. So I have a vibration problem possibly related to the tires being cupped. I have researched and am unclear as to what component(s) are worn causing the cupping? Or what causes cupping?
Tires are Continental DWS06 stock size.
255 35 20.... "w" is visible on tread so they are in fine shape. Alignment is up to date. Vibration really starts at 60 but very obvious at 73-77 and continues up to 120. any advice would be appreciated

14sapper14

You might have bent wheels. I had three. Same size tire so no rubber at all. It doesn’’t take a lot. Cupping would be from low pressure always. Should be 40 min. Sticker on the door jam says 42 front 46 rear I believe . Start with pressure, then new tires because cheapest but it sounds like my old issue. Unfortunately my 5 spokes are 1500 a piece. Hope that helps.