go to Lowes and get one of those industrial floor doormats you see inside office buildings etc. The one I got is a foot too big so when our 100 lb German Shepard is there I have the overlap towards the back hence tailgate is covered when down. When dog isn't riding then leave flap towards back seats. Works great and is carpeted so sucks up hair! Throw it in driveway and you can vacuum it or if you're lazy you throw it out and get another (~$8). It's rubber on bottom so good for ski stuff, mud etc as well.

joe 2006 4.4