Allison behind Cummins 6.7

[coker6303]

Ok, looking for some opinions about putting a 6speed allison built with a PPE stage V kit behind my brothers 2010 6.7 cummins. Pretty much bolt in ready coming from a guy who set it up for a conversion but dropped the project.

It's either this or a 48rfe and I would rather him have the 6 speed allison for daily driving and towing. I think it would be a better fit. Truck will not be a race truck, just want to be able to hold 500-600hp reliably on the street and the 68rfe won't cut it.

I guess i'm just curious about the low rpm torque curve of the cummins strapped to the allison.

 

[Mike L.]

Ok, looking for some opinions about putting a 6speed allison built with a PPE stage V kit behind my brothers 2010 6.7 cummins. Pretty much bolt in ready coming from a guy who set it up for a conversion but dropped the project.

It's either this or a 48rfe and I would rather him have the 6 speed allison for daily driving and towing. I think it would be a better fit. Truck will not be a race truck, just want to be able to hold 500-600hp reliably on the street and the 68rfe won't cut it.

I guess i'm just curious about the low rpm torque curve of the cummins strapped to the allison.

Don't think there is a controller for the 6 speed Alli available.

 

[JustinD]

68rfe won't cut it? Why??

 

[Mike L.]

68rfe won't cut it? Why??

Same trans as a Jeep Liberty only slightly bigger.

 

[JustinD]

Really? I thought those Dodge trannies were pretty good? Is that just in the 6.7 trucks?

 

[Maricopaagent]

bigger updated 727 with OD was my perception of it..(but im no tranny guy)

is it the same tranny behind the ALL IMPRESSIVE Gotta Have a Hemi?

 

[Dirtymaxx03]

all dodge trannys suck

 

[duratothemax]

bigger updated 727 with OD was my perception of it..(but im no tranny guy)

is it the same tranny behind the ALL IMPRESSIVE Gotta Have a Hemi?

No, you are thinking of the pre-6.7 cummins transmissions (47rh, 47re, 48re, A618, etc)

As Mike said, the 68rfe is a joke (check out the cummins forums and guys who are running >500hp in their 6.7's), and unlike the 48re, it "cant" be built/made bulletproof. All of the big power 6.7 guys are swapping to built 48re's or manuals...

 

[Subman]

Don't think there is a controller for the 6 speed Alli available.

Yeah Mike what is with that? Bennett at Performance Authority is currently doing a 6.7 swab into what was a 7.3 one ton Ford with an 6 speed allison behind it and found out the same thing why no 6 speed controller?

 

[Colt]

Destroked can sell you the kit to put that Allison 6 spd. behind that 6.7 and the controller. They are in Broomfield, Colo and convert alot of Fords to Cummins with tranny choice of customers. See if that gets you done it's also advertised in back of last month's Diesel Power mag.

 

[TheBac]

I drive a 6.7/6spd Alli combo every day at work. Chassis is Freightliner, so that might be a place to start to find a controller/harness.

 

[Bryce418]

I'm not sure if destroked has a 6 speed controller but I know for sure they can hook you up with a 5 speed.

 

[coker6303]

I'm not sure if destroked has a 6 speed controller but I know for sure they can hook you up with a 5 speed.

This is the setup the guy was using. I asked for more details but he hasn't answered yet

---------------------------------
08 LMM Chevy CCSB
Relentless Diesel trans
JoshH EfiLive tuning
554hp 1014ft-lbs 7/30/11

 

[Mike L.]

Destroked can sell you the kit to put that Allison 6 spd. behind that 6.7 and the controller. They are in Broomfield, Colo and convert alot of Fords to Cummins with tranny choice of customers. See if that gets you done it's also advertised in back of last month's Diesel Power mag.

Do your homework before you post. Destroked will NOT build a 6 speed stand alone till he has at least 10 orders. When Scott (Destroked) buys his parts he has to buy in the thousands. He cannot afford to build a couple of units after spending many thousands.

 

[Bryce418]

Scott has some pretty nice setups running around. I have seen a few Allison/6.7 combos he has done in f250/350's and they look almost factory

 

[THEFERMANATOR]

There has been at least one 6 speed stand-alone that I am aware of, and so far it ISN'T working 100%. The only real viable option for stand-alone is to go with the DESTROKED kit for a 5 speed, then convert the trans to a 5 speed with external NSBU switch, and then put a SUNCOAST 6 speed conversion kit in it. I know MAXPF is working on one right now for his 12valve, but I haven't heard any progress from him lately. If your not concerned about having good shifts for a daily driver, then you can always go with a medium duty calibration in it which will be locked in tow/haul mode all the time. Problem is that the ALLISON dealer must verify that it is going into a 1 1/2 ton truck or bigger before they will work on it is what I was told when I tried to get them to flash my TCM to a medium duty cal when I did my swap. They told me it was due to the sale conditions with GM when they sold off ALLISON but retained the 1000 series for the pick-ups.

Have you considered going to the AISIN ALLISON knock-off out of a 4500 series?

 

[Bryce418]

The 68rfe is an Aisin trans.

 

[JoshH]

The 68rfe is an Aisin trans.

That's the first I've heard that. You sure?

 

[Bryce418]

I stand corrected. But I still don't feel the Aisin will hold any real power, they don't hold up terribly great behind a 5.2 4 cylinder Isuzu.




From wiki


The 68RFE was introduced in 2007 Ram 2500 and 3500 Pickups with the 6.7L Cummins ISB Diesel engine. It is not currently used in 2007-present Ram 3500/4500/5500 cab chassis. Transmission in these models is the Aisin AS68RC.

The basic design and operation is the same or similar to the 45 and 545RFE counterparts with the following exceptions:

larger bellhousing with different bolt pattern and cutout to accommodate diesel engine
modified internal components to handle increased torque of diesel engine
revised gear ratios and Transmission Controller programming for larger application
no 2nd gear prime for downshifting like the 45RFE and 545RFE transmissions

 

[THEFERMANATOR]

As far as I understand it yes.




From wiki


The 68RFE was introduced in 2007 Ram 2500 and 3500 Pickups with the 6.7L Cummins ISB Diesel engine. It is not currently used in 2007-present Ram 3500/4500/5500 cab chassis. Transmission in these models is the Aisin AS68RC.

The basic design and operation is the same or similar to the 45 and 545RFE counterparts with the following exceptions:

larger bellhousing with different bolt pattern and cutout to accommodate diesel engine
modified internal components to handle increased torque of diesel engine
revised gear ratios and Transmission Controller programming for larger application
no 2nd gear prime for downshifting like the 45RFE and 545RFE transmissions

In red it states the 3500 C&C, 4500, and 5500 use the AISIN AS68RC which is NOT the same as the 68RFE. They are COMPLETELY different trannies from each other sharing NO parts that I am aware of.