JIMNLIN wrote:
I didn't see it mentioned and gotta' ask but which year model G56 did you go with.
The newer G56 behind the 6.7 have different gear ratios and the DMF.
I have a '03 with the NV5600. The inline 6 cyl Cummins/Jacobs and the 6 speed manual tranny is the sweetest set up for serious hauling (commercial) I've ever had.
It was out of an 05 so it's got the shorter 0.79:1 6th gear resulting in higher revs, but it doesn't seem to affect mileage -- in fact everything that I've been reading indicates just having less parasitic loss in the manual improves mileage 2mpg on the highway. I have too few miles on it thus far to know how the mileage is looking for me. The G56(AE) out of the later 6.7's have a 0.74:1 6th
The guy I traded with had already upgraded to a Southbend dual-disk dual friction SMF clutch with low miles, so I went ahead and just put that clutch into my truck so I didn't have to deal with the DMF, thankfully. Although, it's half-ceramic so it can get kind of grabby if I'm trying to ease into anything with any kind of slip. I'm getting used to it now after a month.
rhagfo wrote:
When my NV4500 gives up OR I find a sweet deal on a G56 I will do it to my 01! The 5 speed has a big jump from 3rd to 4th would to have that extra gear!
GREAT JOB!
I like the gear splits on the G56. Seems great for towing a heavy load (which I have yet to do with my new setup) It should be a much easier swap for you than going from an auto to a manual. Probably just the trans mount, adjusting driveline length if the lengths vary at all and adapter plate, starter and flywheel/clutch. Looks like it has the same output spline count for as the G56
