Featured Image show full image like featured slider

Hello, I am wanting my featured image to show the full image on the category page like it does in the featured slider. I thought I had this fixed, but all the new posts I add only show part of the image. I don't remember how I fixed it before. My website is 1stattack.com, but if you go to the following link you will see what I am talking about. http://1stattack.com/category/fast-attack-trucks-built/