car 3d model from blender not properly importing

I have car 3d model in Blender that i need to make drivable, i already rigged it and organise everything, wheels FR, FL, RR, RL, Body. Wheels is rigged properly, origins in the middle of the wheels and they are spin/rotating/turning correctly in Blender. When im importing car in Unreal Engine its just materials, body, wheels, its not one object with wheels that i can work with.