Vehicle Assertion failed: NumChassisShapes >= 1

I’m trying to create my own vehicle. When I try to test it however I get this error:

D:\BuildFarm\buildmachine_++depot+UE4-Releases+4.4\Engine\Source\Runtime\Engine\Private\Vehicles\WheeledVehicleMovementComponent.cpp(339): Assertion failed: NumChassisShapes >= 1

Can anyone give me advice on this error? Vehicles in general appear to lack documentation.

Notes: My mesh has 5 meshes and I’ve set up 4 wheels, so I wouldn’t expect it to fail the check.