ok well I have a 2000 DD and need some help if you wouldnt mind. I have rought 78k on my truck and recently I am having a slight miss at idle. So I did the normal thing and replaced all plugs and wires and the whole nine yards. Well this didnt help so off to the mechanic I went. the local D dealer said carbon build up is a possible problem or a cracked head. I have a 5.9 with low unabused miles a cracked head seems unlikely. Thats issue one, second would be a skip in the rpm's when cruis is set on the interstate whats the deal with this and it isnt all the time its very intermitent. These are the only problems I am having with my truck. this is soo irritating especially the miss in traffic it wouldnt bother many but I am very perticular on the way my vehicles run and on maintenance. if you could offer some other insight that my dealer is not that would be great

thanks