There is vehicle included in the base BeamNG.drive game. Any reference to a "Captiva update" refers to a third-party mod (user-created). The quality, physics accuracy, and update status of such mods vary significantly.
Here is the breakdown:
If you are tired of perfect race cars and want to experience the sheer dread of understeering into a guardrail in a top-heavy Korean crossover, this is the mod for you. Just be prepared to call a virtual tow truck. beamng drive chevrolet captiva upd