How to move the character relative to the camera?

I use the camera's angles to base my movement off of. I then multiply the inputs by the camera's vectors to produce movement in the camera's direction. This works if I use transform.Translate(motion*Time.deltaTime), but controller.Move() does not seem to work with or without transform.TransformDirection(motion). Am I screwing up world versus local somewhere here? Translate works fine but the move function goes at off angles.

 start(){
 controller = GetComponent < CharacterController> ();
 cameraAim = GameObject.FindGameObjectWithTag("MainCamera").transform;
 }
 update(){
 Vector3 input = new Vector3 (Input.GetAxisRaw ("Horizontal"), 0, Input.GetAxisRaw ("Vertical"));
 Vector3 forward = new Vector3(cameraAim.forward.x, 0, cameraAim.forward.z);
 Vector3 right = new Vector3(cameraAim.right.x, 0, cameraAim.right.z);
 Vector3 motion = forward*motion.z + right * motion.x;
 motion = transform.TransformDirection(motion);
 controller.Move (motion * Time.deltaTime);
 }