I removed the stock bed from my 04. 5 Dually and installed a CM steel flatbed. I was having interference problems with the GN horse trailer that I pull hitting the bed rails when I drove places that I shouldnt have. Now with the flatbed I will have NO issues with contact and causing damage to the trailer or truck. The first thing I noticed is how much better the truck handles in the twisties with the trailer behind, some of this may be the extra weight of the bed, but I assume that the rear frame is now much stiffer and that helps the handling. This is VERY pronounced both my wife and I notice the diffrence. The next is how much quieter the truck is when towing. Less road noise and a lot less resonance from the exhaust. I assume that this is because the stock bed is just a big amplifier of all of the viberation and noise that is always there. I also have less wind buffeting, I think that this is because the wind that would get trapped after spilling off of the nose of the trailer now has a smooth exit rather than tumbling in and around the stock bed. . I am a VERY happy camper now. . Great upgrade to the old truck.