right now looking at an 04 and 03 1-ton dwr. the 04 has the 600 and the 03 has the 555 ctd. so which one????? the trucks themselves are the same with their options. i have heard and read about the 555s and their better mileage than the 600s and 610s due to emisions changes.

so if ya'll could help the ol' snuffdog out i, would much appericate it.


thanks........

 

I can not help you much, have not driven an 04. I think the 6 speeds are different too, 03 was nv 5600(reverse up and left) and then they went to the g56(reverse down and right). The g56 is geared lower , I think. Not Sure when they swichted forsure though. Other than the milage thing thats about all the things I have heard.

 

G56 was not availabe until the '05 models. It's a crap shoot...some folks got the NV-5600 some got the g56. Prior to '05 all 6 spds are the NV5600.

My friend has an '05 dually with the 5600 and 3.73's. His is the 325/610. I have an '04 305/555 SRW but the same 3.73's. I get about 2-3 MPG better than he does both empty and towing. I just got a tad under 16 MPG towing 8K..he usually get's 13-14 with the same weight load.
Power wise...I can't really tell a difference. His is definitely a little quieter...but beyond that they feel about the same to me.

 

As far as fuel mileage don't beleave everything you read, toooooo many variables between trucks and people. Everyone said the same about the 3rd generation trucks compared to the 2nd generation trucks, the 3rd gens will get worse fuel mileage blah blah blah. My 05 gets 2 MPG more than my 1999 got. Both are 3500 DRW QC 4X4 long boxes. Oh and the 99 had 3:54 gears compared to my 05 with 3:73 gears so the 99 should get better mileage, not. I also drive my new truck harder than I did the 99.