We had a crew cab long bed 2WD dually and it was totally useless in mud or snow. It was DH choice to forego 4x4 on that one. When we traded I went to dealer and brought him his new dually, same thing except Duramax and 4x4. He never argued and it's his all time favorite truck. Trying to figure how to take it with him when he dies. LOL We had to pull the old 2x out with a tractor on a residential job site in minimal mud more than once, not the new one. With all this being said, the 4x4 is great for forward motion in slippery conditions but NOTHING will stop on a dime in ice, 4x4 or not, chains, maybe a little better. The only thing we drive in bad snow is our Toyota FJ and are still super careful stopping.