Character rotation is jittery

I am trying to write a player controller for my character and for the most part it works but I have a problem with stuttering.

In my hierarchy, The camera is separate from the player, and the CameraPivot and GunPivot are attached to the player.

When I rotate on the Y-axis it seems fine, but rotating my character to look up and down (X-axis) makes the movement of the gun, hands and camera stutter or jitter or out of sync.

I Know there are many other topics on this, but I was not able to find anything that works for this. I have tried using LateUpdate, and FixedUpdate(with Fixed deltatime) (Neither seem to help). Also I have tried quaternion or slerp, but unsure of how to actually implement them into my code.

Any help will be appreciated. Thanks.

 void Update () {
     //Player Move Stuff
         Forwards = (Input.GetAxis("Vertical")) * runspeed * Time.deltaTime;  
         Sideways = (Input.GetAxis("Horizontal")) * sidespeed * Time.deltaTime;  
         transform.Translate( new Vector3 (Sideways, 0, Forwards));
         RotatePlayer = Input.GetAxis ("Mouse X") * TurnSpeed * Time.deltaTime;
         transform.Rotate (new Vector3 (0, RotatePlayer, 0)); //Rotates the player
     //player Camera Stuff
         PlayerCamera.transform.position = new Vector3((CameraPivot.transform.position.x),(CameraPivot.transform.position.y),(CameraPivot.transform.position.z)); //Camera follows the pivot location
         RotateCamY += Input.GetAxis ("Mouse X") * TurnSpeed * Time.deltaTime;    
         RotateCamX += Input.GetAxis ("Mouse Y") * LookUpDownSpeed * Time.deltaTime;    
         RotateCamX = Mathf.Clamp (RotateCamX, Xmin, Xmax);        
         Vector3 PivotVector = new Vector3 (-RotateCamX , RotateCamY+180, 0);
         PlayerCamera.transform.eulerAngles = PivotVector; //Rotates the camera
         CameraPivot.transform.eulerAngles =PivotVector;  //Rotates point the camera is attached to 
         GunPivot.transform.eulerAngles = PivotVector;   //Rotates point the gun is attached to
     }