View Full Version : G56 or NV5600 swap

03-15-2009, 11:39 AM
I have had it with my 68rfe. I am going manual. Which one to swap in is up in the air. Which would you swap in and why. Don't say 4500 either. Truck is a 07.5, 6.7L, DRW, QC. Warranty is out so I'm on my own.

I have the suncoast mega kit and their sprag but have made my mind up to go manual. I will be selling those parts along with parting out the tranny.

03-15-2009, 12:08 PM
I have not seen any problems with the g56 except bad clutches the nv does have some issues with shafts I think and the g56 came in these trucks so thats what I would go with but they are not cheap either.

03-15-2009, 10:52 PM
But if you pull Put a 5600 in. The aluminum cases in the G56's dont like pulling with over 600ish hp.

03-15-2009, 11:52 PM
Lots of guys are losing 4th gear in the G56's. Kinda depends on what you do with the truck. If you sled pull or drag race I would put in a NV5600. If not I would put in a G56.

03-16-2009, 08:14 PM
I'm not in the pulling. Don't get me wrong, I love watching it but this is to pull my rock crawler. I just want something that won't leave me on the side. I have not had any luck with the auto. It's been rebuilt 3 times and with all the sun coast stuff ( mega kit and upgraded sprag). At first I had the mega kit and went through 2 sprags. I upgraded the sprag and now it messed up the planetaries. It's time to move on.

03-16-2009, 11:13 PM

03-17-2009, 05:07 PM
I found a 2005 G56. What if any problems could I run into putting it in a 2007.5 6.7?
Here is what I am thinking:
Will it bolt up? YES
Have to modify interior for shifter? YES
Have to get clutch pedal assembily? YES
Slave cylinder? YES
Driveshaft modification? YES
Crossmember modification??????????????????
Reprogram the computer? YES

What else am I missing?

smokin 6.7
03-17-2009, 08:57 PM
sbc dd 3600 would prob be the only other thing