I drive a 2002 Ford F-150 Lariat 5.4L V8. About a week or two ago my wife was using my truck, and she put it in reverse and said my truck felt like it was chugging while backing out the drive way. Later on that day I reversed it out the drive way and it was doing that chugging she was talking about. It doesn't do it when driving forward. Just in reverse, I noticed it's worse when I hit the brakes lightly. Due to my busy work schedule lately I haven't had much time to get under the truck and check what's wrong. If you could give me some ideas what to look for so I can find an easier conclusion to the problem, thanks.