Welcome to my guide for G56 transmission swaps on 2006-2012 & 13-18 Dodge Cummins trucks. I will be posting some step-by-step instructions, tips, and resources to successfully swap your transmission.
Note: This website is from personal experience and a work in progress. More to come soon. Hoping to add detailed pictures and videos in the future.
Website last updated: 10/12/24 // Update Note: Finally trying to get some work done on the website, Got Menu fixed, added Home page & Parts List page. More to come.
Update 10/6/24 – **More New information added to Electrical Guide page** – I’ve added more information / pictures. More to come!
If you need any assistance my contact information is at the bottom of this page.
You can also find myself (and many others) willing to help on the Facebook group called “G56 Swap How To“. – Aaron Aaron
General information:
48re vs 68rfe vs G56 Transmission Length:
48re = 26.5in long
G56 = 29 1/4in long
68rfe = 27in long
48re vs 68rfe vs G56 Transmission adapter plate:
G56 adapter plate is 6cm wide;
48re adapter plate is 6cm wide;
68rfe is almost 7cm wide. *You WILL need g56 or 48re adaptor plate*
07.5-12 68rfe adapter plate will *NOT* work. I was told that 13+ will work. I have not confirmed. I will try to confirm this*** (If you know 100% it will because you used yours, please let me know).
PRO TIP for 07.5+
The automatic(68rfe) adapter plate on 07.5+ had support brackets connecting to the sides and back of the motor. The bracket to the top of the motor makes stabbing the transmission a pain, pull off the bracket before trying to stab the transmission!
48RE vs 68rfe vs G56 Output shafts / T-case output shaft size:
2007.5 6.7l np273 T-case NPG Part Number 51169: 29 Spline
2007 5.9l np273 T-case NPG Part Number 51169: 29 Spline
More info coming for tcase.
48RE vs 68rfe vs G56 Transmission Crossmember:
The 48re/68rfe crossmember & trans mount is the same.
The G56 crossmember is the same as 48re/68rfe. *However, the transmission support bracket is different!! You will need a new trans mount (Not crossmember)
ECM Flashing:
Efi live: I’m told they can make a tune, reach out to their support to get more information
Smarty: Call and talk to one the guys from Smarty. They will send you a manual recovery file, it takes about 2-3 days to get from smarty and will cost you $120-150. I used my Smarty Sr to do the flash – Contact Smarty Support
Note: Once you flash the ECM you will have to go back and update your smarty back to being a tuner – Smarty will not let you re-install a DPF/EGR delete tune! You will need to find the files online to put your smarty back to a Non-emissions tune.
PARTS LIST:
Drive Train:
View the Parts Lists HERE – This is not an official list, but it will get you started. I’m working on getting more Parts & Links. If you have any ideas, please send it to me so I can get it posted.
Parts List
Electrical Guide: (06-12)
View the Electrical Guide HERE – This will give you the steps needed to start the truck & fix reverse light/4lo issue.
Electrical Guide
FLUIDS:
G56 Transmission: 7qts manual transmission fluid
T-Case: 2qts ATF
Specialized Items/Tools:
14mm Allen (G56 fluid drain)
Cummins barring tool
E12 Socket
Clutch alignment tool (SB 3250 kit)
Loctite
High temp RTV (Re-sealing G56 shifter)
If you need any help, please reach out to me via email [email protected] / I’ve personally assisted in 20+ swaps on 06-18.
If you have any tips, tricks, information or experience you would like to share feel free to send it over, I will include it on the website.