Looking to Replace my 2017 2500 68RFE to 2017 3500 Allison tranny

[Robert 2017 2500]

I was thinking on replacing my 68FRE to 3500 Allison tranny same year 2017 2500 6.7. Will it hook right up or will there be some mods. I found a few from 1500 to 2000 for my year. Not worried about the conduction since their bullet proof. Hate the 68RFE. Its banging between 3 & 4. when I reach 32-39 I have to let up the on the pedal so it shifts smoothly. Thank god I don't do any heavy hauling. Later I was also thinking on putting Highway gears since I don't use it for hauling for better mileage. Any info would be appreciated.

 

[crash68]

I was thinking on replacing my 68FRE to 3500 Allison tranny same year 2017 2500 6.7.

There is not Allison transmission for the 3500 or the 4500 and 5500 either.
Did you mean to type Aisin transmission? It would take a different transmission controller and wiring harness along with reprogramming the ECM to work with the TCM.
Your truck already has 3.42 gears in the axles, only ratio the 2500 CTD offered that year.
Your probably better off getting a custom built up 68RFE, there's a bunch of companies that make the trans hold up to lots of power and shift smoother.

 

[Racer9]

Actually, there is s a swap kit from ATS https://www.atsdiesel.com/allison-conversion but I doubt it is inexpensive.
A better idea may be to fix the issues in the 68RFE

 

[Brandon-w]

I'm in the process of doing this on a 12v cummins. You need adapter plates for the bellhousing, the transmission, a special torque converter for low rpm, stand alone harness and tcm, either a gm t case or an older Dodge t case that has the PTO port in it I forget which model it is but luckily I already have it. You need lines and an external radiator driveshaft shorten and lengthen and then a tune. It's going to be a solid unit once it's done.
Hope you have about 8-12k laying around.

 

[Racer9]

Back when I was into diesel a lot, I remember that GM guys were switching to built 48Rh for the pulling trucks because the Allison wouldn't hold up.

 

[jejb]

I was thinking on replacing my 68FRE to 3500 Allison tranny same year 2017 2500 6.7. Will it hook right up or will there be some mods. I found a few from 1500 to 2000 for my year. Not worried about the conduction since their bullet proof. Hate the 68RFE. Its banging between 3 & 4. when I reach 32-39 I have to let up the on the pedal so it shifts smoothly. Thank god I don't do any heavy hauling. Later I was also thinking on putting Highway gears since I don't use it for hauling for better mileage. Any info would be appreciated.

You may want to look into fixing your 68RFE. I've had 2 of them behind the Ram Cummins, and both are very smooth shifting, pulling or not.

 

[mtnrider]

I assume you are tuned because that sounds like poor tuning to me, maybe it's running locked shifts?

Either way, you can build a bullet proof 68 a lot cheaper then an allision swap and those are not immune to breaking either

 

[nlambert182]

I assume you are tuned because that sounds like poor tuning to me, maybe it's running locked shifts?

Either way, you can build a bullet proof 68 a lot cheaper then an allision swap and those are not immune to breaking either

This is what I'm thinking too....

I've owned a couple of 68RFEs and all have shifted and performed flawlessly with or without a load behind it. I've deleted all but my current truck and haven't had any issues either. That said... I don't turn up the HP nor tune the trans.

If my 68RFE does fail, I'll slap in a built one before I'd go through the headache of trying to make some other one work in it.