I can't get framerate independence to work...

So I have a movement script for a rigidbody. I use Time.deltaTime for everything but it definitely isn't framerate independent. Lower framerates make you move faster, and higher framerates make you move slower. Check out my code.

 #pragma strict
 
 var MovementSpeed = 7000;
 private var MovementVer : int;
 private var MovementHor : int;
 private var distGround : float;
 var MaxSpeed : float;
 var jumpSpeed : float;
 
 function Start(){
     distGround = collider.bounds.extents.y;
 }
 
 function IsGrounded() : boolean {
     return Physics.Raycast(transform.position, -Vector3.up, distGround + 0.1);
 }
 
 function Update() {
     //setting up the movement variables
     MovementVer = Input.GetAxis("Vertical") * MovementSpeed * Time.deltaTime;
     MovementHor = Input.GetAxis("Horizontal") * MovementSpeed * Time.deltaTime;
 
 
     //Stops the character from sliding around when you aren't moving
     if(Input.GetAxis("Vertical") != 0 || Input.GetAxis("Horizontal") != 0) {
     
         rigidbody.drag = 1;
         }
     else{
         rigidbody.drag = 10;
         }
     if(Input.GetAxis("Jump") && IsGrounded()){
         rigidbody.drag = 0;
         rigidbody.velocity.y = jumpSpeed;
         }
     if(IsGrounded() == false){
         rigidbody.drag = 0;
         }
     
     if (IsGrounded() == false){
         MovementSpeed = 2;
         }
     if (IsGrounded() == true){
         MovementSpeed = 7000;
         }
 }
 function FixedUpdate () {
 
         rigidbody.AddRelativeForce(Vector3(MovementHor, 0, MovementVer));
         
 }