i am in the process of purchasing a 2003 dodge 3500 cummins dually, they have dropped the price down 1k due to transfer case had been ran dry and front top ball joints are done and back breaks are metal to metal. but regardless they cut me a good deal so i couldnt pass it up and i can also do all the work myself. the question i have is what kind of fuel mileage should i be seeing and what can i do to get better mileage? and on a side note im wanting to trade out the rear end from drw to srw. is there anybody else looking to swap from srw to drw? the pict of my truck is next to my profile name.

 

intake... exhaust....and a eco tune would help mileage.