hm don't think the roof rack is standard, although it could explain the size of the difference. i'm thinking besides the rack, the big source of discrepancy would be wheels. the new EX90 with aero grille block and aero wheels got a 0.29, so 0.30 with nearly the same shape but not these two mods seem...

Looking at the reporting/literature on the SPA xc90, the drag coefficient was reported at 0.30 early on, but this was altered to 0.33 after 2017 or so. Does anyone know the cause of this discrepancy and whether any material changes to the design caused it, or was it just updated testing/CFD meshing ...