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After a lot of research, I managed to track down a 6 speed Allison 1000 from what I believe was a 2007 6.6 Duramax. The trans itself is July 2007 build. It's a 2 wheel drive trans but that will have to do for now, given the circumstances. It's missing the harness (it shouldn't be hard to buy one online?). I'm not sure about the TCM if it's there or not, but would it be a problem if I bought the trans without it? I don't think I'll ever reflash the stock TCM myself or even find someone who would do it without messing things up first. From my understanding I can buy an aftermarket standalone controller, that would come pre-flashed, am I m
A stand-alone harness and TCM can be purchased separately if necessary. If you buy one of the medium-duty controller setups, then they will supply a harness and suitably flashed TCM as needed. That is all relatively straightforward. It just costs money.

My question is, would I have any issues fitting this specific trans to my Cummins (It's an 89 12 valve non-intercooled, intercooler will be added later)?
It's been done umpteen times. Why do you think there would be a problem fitting it to your specific engine?

And what parts would I also need to make the swap. I know this may have been asked a few time before but I can't seem to make a definitive list of parts that I will need to make the swap. Other than the trans adapter and necessary flexplate/bolts, what else would I need (TCM, wiring harness,...etc)? What about throttle input for the trans?

The engine and trans are going into a 1978 Dodge truck, so there shouldn't be any major electrical issues, everything is pretty much mechanical, so I shouldn't have to hack into the wiring harness to make it work with an ECU/ECM.

Any input would be appreciated, I'm about to pull the trigger on the trans but I need to make sure I have everything else to make the swap go as trouble-free as possible.

Excuse the low quality pics, I was sent them by the guy who's selling. I'll go see it in person if it's the the right transmission.
This has all been covered numerous times in this thread, but here it is again:

1) You need to mount the transmission to the engine. You have two basic options: Either use SAE #3 (SAE #2 is too big for most pickups) or the GM bellhousing.

If you choose SAE#3, you need the SAE#3 flywheel housing for a B series front gear train engine, SAE #3 bell housing for the Allison, SAE #3 flexplate and converter/flexplate pilot for the Cummins B series, and the SAE #3 flexplate-to-converter mounting ring (a conical shaped ring that attaches the converter to the flexplate). That is five components. You also need the particular starter for whatever SAE #3 housing you get. I would highly recommend ONLY using an SAE #3 housing with a left-side mount starter to avoid exhaust interference. You will likely have to do some removal of various mounting bosses and protrusions on the flywheel housing. Not a big deal.

If you choose to go the GM bellhousing route, then your only realistic option is the Destroked flywheel housing and flexplate kit. It uses the GM bellhousing already on the 07 Allison you are looking at. The other item needed is an expensive Ford 6.0 Powerstroke starter, which mounts on the right side. You can get the whole kit and kaboodle from Destroked; adapters and electronics for stand-alone operation. I don't personally care for the Destroked stuff (or anyone else's stand-alone solutions for that matter), but it more or less works and is the easiest way from A to B if you want to stick with the GM bellhousing and not shop separately for your electronics. Note that you CAN use the Destroked adapter hardware and another outfit's electronics, or vice-versa. Most guys choose a single source for everything though, for obvious reasons.

2) You need the electronics. ALL controllers will use the OE Allison TCM. There's three basic methods in use: the first is to use a medium duty OS in the TCM which takes throttle inputs directly from a potentiometer-type TPS. Every one of these I have driven shifts just like a medium duty truck, which is to say it shifts like a GM Allison TCM stuck in tow/haul mode. I'm also pretty sure they have no option for a 4WD low range shift schedule. This isn't tragic, but it's nice having a softer shift schedule with different shift points in low range, as well as being able to run the output speed sensor on the t-case output rather than scabbing it into the trans-to-tcase adapter.

The second control option is to use an 8.1L gas OS in the Allison TCM. This gives all the goodies of a GM TCM cal, and allows you to use a common off-the-shelf Cat (or Ford, according to some folks) TPS with a PWM output. The two main complaints with this option are lack of tow/haul without wiring in a compatible BCM or some other box to communicate tow/haul button requests to the TCM, and the fact that the TPS input doesn't give full range on the TCM input. As mentioned, tow/haul can be done with extra boxes and wiring. The apparent limit on TPS input range can be worked around with proper scaling of the calibration tables. It isn't a perfect option, but it does get the job done and I have a few trucks out there running with this setup that I did in years past.

The third option is to use a TCM with the GM OS used in Duramax applications. This requires an interface controller capable of sending the required signals via GMLAN to the TCM. I'm not sure if the Destroked kit uses this method, or method #2 with an auxiliary box, but either can work. If the interface is done correctly, you will have access to all features of the GM OS in the Allison TCM. If it's done correctly AND you have electronic engine controls then you will also have defuel capability, which massively increases the amount of torque the trans can reliably handle.

That's pretty much it.
 

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Yes. Do you have something constructive to add?
 

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Yes, the shifter will be specific for an Allison.
NO IT ISN'T! Please stop posting inaccurate information! If you don't know, then either say you don't know, find the correct answer and post it, or simply don't answer the question.

The six speed Allison can use any six-position shifter with either 3-speed or 4-speed GM-spaced detents, adjustable detent positions, or no detents. Chrysler and Fords use a shorter rotation between park and reverse, so any tightgly gated shifter made for them won't work on the Allison. Most older vehicles with column shifters had no detents on the column shifter itself. It used the detent positioner in the trans itself (the "rooster comb") to locate each shift position. The PRNDL indicator may not exactly line up on a non-GM vehicle, and GM vehicles with 4-forward-speed PRNDL's won't use to the lowest indicated range if properly stopped. See The complete Allison 1000/2000/2400 info and swap guide thread for info. The 6 speed Ally actually has seven detents, but the last one isn't used and an external stop should be installed on the trans or shifter to prevent dropping into the unused position.

If you are using a shifter with built-in detents, whether column or floor, it needs to be compatible with GM 3 or 4 speed automatics. Most aftermarket shifters are "universal", and are capable of being used on common GM 3 and 4 speed transmissions, so they will work fine on the Allison.

If your Dodge column shifter is like the one on my OBS GM pickup in that it has no detents, then it can be made to work. In all likelyhood you won't have to change anything, but it is possible you may have to shorten the trans shift lever a bit. You might have to reverse the linkage, or even convert to cable operation. Those are all possibilities one must confront when doing swaps. Things are rarely all bolt-on.

The 3000 and 4000 series transmissions used completely electronic shifters. Even the "lever" shifters for these transmissions have no mechnical connection to the trans. The 1000/2000 series REQUIRE a mechanical manual shifter connection. The only electronic shifting available is when the manual shift lever is in (M)anual mode, at which point push-button tap shift is enabled.


There are some aftermarket models possibly. The controls are electrical. If you could locate the SAE3 parts, that may be cheaper than the Destroked adapter setup. You'd need the SAE3 engine block adapter, flex plate assembly, and starter for a Cummins 6bt. Then you'd need the SAE3 bellhousing for the transmission which is an Allison part. The 1000 and 2000 series transmissions both used that. If your Allison had come from the GM medium duty Kodiak line it would have had the SAE3. Don't know the part number for that housing, but if there are any GM medium duty truck dealers over there they could find it. The parts on the other side would all be Cummins.
Any Allison dealer can supply the SAE #3 bellhousing, and for a LOT less money than what GM wants for the same part. Be advised that there are two different SAE #3 housings. One has integral cooler ports and an integral filter boss, while the "other has a separate oil cooler/filter adapter plate that mounts to the bottom, and that plate has the cooler ports and filter boss. It also has more ribbing than the "one piece" integrated housing. The latter housing doesn't come with the plate and plate-to-housing gasket, which must be ordered separately. Most apps use the one-piece housing, and it is certainly the cheaper option between the two.
 

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When I said the shifter was specific for the Allison, I was not speaking of adapting the Allison to an in vehicle steering column shifter. All the shifters you see in medium trucks are specific for that transmission. How many companies make a kit to use the old Dodge TF727 shifter with a 6 speed Allison? I couldn't find any.
 

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When I said the shifter was specific for the Allison, I was not speaking of adapting the Allison to an in vehicle steering column shifter. All the shifters you see in medium trucks are specific for that transmission. How many companies make a kit to use the old Dodge TF727 shifter with a 6 speed Allison? I couldn't find any.
It seems you misunderstand the difference between the different Allison series and the shifter requirements. The 3000 and 4000 series have completely electronic shifters. They can be either push button, lever (t-handle style), or manufacturer specific. In the latter case, Freightliner, for example, uses their same stalk shifter for both Allison automatics as well as Eaton automated manual transmissions.

The 1000/2000 require use of a mechanical shifter. The rooster comb (detent lever) inside the transmission has the same pattern spacing as GM 3 and 4 speed automatics, such as the TH400, TH350, 4L80E, and 4L60E. ANY shifter capable of operating one of those transmissions can operate a 1000/2000 series Allison.

The Chrysler and Ford automatics are similar to GM units, except for the detent to detent spacing. That said, as long as the Chrysler or Ford shifter doesn't have internal gates or detents, which most don't, then they are easily adaptable to the Allison. The PRNDL indicator may not exactly line up, but that is an easily solveable problem.

None of this is rocket science. If someone is doing an Allison swap, the shifter will be the least of the problems needing to be solved.
 

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Discussion Starter #47
A stand-alone harness and TCM can be purchased separately if necessary. If you buy one of the medium-duty controller setups, then they will supply a harness and suitably flashed TCM as needed. That is all relatively straightforward. It just costs money.
I'll probably go aftermarket, just to be on the safe side, it doesn't cost much from what I found out. Most of the junkyards here are exposed to middle east sun (think Nevada/Texas). It might seem intact, but the insulation is most likely dry and falling apart.

It's been done umpteen times. Why do you think there would be a problem fitting it to your specific engine?
Yeah, I now realize I was being paranoid about it. I just didn't want to spend the money on a transmission that would end up being a boat anchor since no one will buy it off me if it didn't fit my engine.

This has all been covered numerous times in this thread, but here it is again:

1) You need to mount the transmission to the engine. You have two basic options: Either use SAE #3 (SAE #2 is too big for most pickups) or the GM bellhousing.

If you choose SAE#3, you need the SAE#3 flywheel housing for a B series front gear train engine, SAE #3 bell housing for the Allison, SAE #3 flexplate and converter/flexplate pilot for the Cummins B series, and the SAE #3 flexplate-to-converter mounting ring (a conical shaped ring that attaches the converter to the flexplate). That is five components. You also need the particular starter for whatever SAE #3 housing you get. I would highly recommend ONLY using an SAE #3 housing with a left-side mount starter to avoid exhaust interference. You will likely have to do some removal of various mounting bosses and protrusions on the flywheel housing. Not a big deal.

If you choose to go the GM bellhousing route, then your only realistic option is the Destroked flywheel housing and flexplate kit. It uses the GM bellhousing already on the 07 Allison you are looking at. The other item needed is an expensive Ford 6.0 Powerstroke starter, which mounts on the right side. You can get the whole kit and kaboodle from Destroked; adapters and electronics for stand-alone operation. I don't personally care for the Destroked stuff (or anyone else's stand-alone solutions for that matter), but it more or less works and is the easiest way from A to B if you want to stick with the GM bellhousing and not shop separately for your electronics. Note that you CAN use the Destroked adapter hardware and another outfit's electronics, or vice-versa. Most guys choose a single source for everything though, for obvious reasons.

2) You need the electronics. ALL controllers will use the OE Allison TCM. There's three basic methods in use: the first is to use a medium duty OS in the TCM which takes throttle inputs directly from a potentiometer-type TPS. Every one of these I have driven shifts just like a medium duty truck, which is to say it shifts like a GM Allison TCM stuck in tow/haul mode. I'm also pretty sure they have no option for a 4WD low range shift schedule. This isn't tragic, but it's nice having a softer shift schedule with different shift points in low range, as well as being able to run the output speed sensor on the t-case output rather than scabbing it into the trans-to-tcase adapter.

The second control option is to use an 8.1L gas OS in the Allison TCM. This gives all the goodies of a GM TCM cal, and allows you to use a common off-the-shelf Cat (or Ford, according to some folks) TPS with a PWM output. The two main complaints with this option are lack of tow/haul without wiring in a compatible BCM or some other box to communicate tow/haul button requests to the TCM, and the fact that the TPS input doesn't give full range on the TCM input. As mentioned, tow/haul can be done with extra boxes and wiring. The apparent limit on TPS input range can be worked around with proper scaling of the calibration tables. It isn't a perfect option, but it does get the job done and I have a few trucks out there running with this setup that I did in years past.

The third option is to use a TCM with the GM OS used in Duramax applications. This requires an interface controller capable of sending the required signals via GMLAN to the TCM. I'm not sure if the Destroked kit uses this method, or method #2 with an auxiliary box, but either can work. If the interface is done correctly, you will have access to all features of the GM OS in the Allison TCM. If it's done correctly AND you have electronic engine controls then you will also have defuel capability, which massively increases the amount of torque the trans can reliably handle.

That's pretty much it.
THANK YOU for this breakdown. This is literally what I was looking for, all the possible options available in one place.
I'll see which one's the best out of the three (cost, parts availability, ease of application..) and go from there.

I just have one dumb question, what exactly is OS and GMLAN short for? It's just so I could look for it in Arabic too if I had to.
 
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