Depending on how much wire youve lost i personally would replace it as the length will set the distance,i would cry if it went out of range on a road and got ran over or had some other control problem and wrecked into a tree,i would rather have the peace of mind of a new unit

lol @ the cat mine doesnt do that but our old dog used to love trying to eat my rc tank in the backgarden,he snapped the barrel twice by trying to pick it up and run around with it lol