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Allison 2000 (July '01 Build) 4x4 conversion

@THEFERMANATOR @Rockabillyrat Thanks to you both for taking the time to respond. I have experience with automatic rebuilds, but none specific to the Allison. Mostly I've worked on 4L80e's, 4L60E's, 4T60's and such. So I am confident in automatic rebuilding, just not the Allison.
The intent is to keep the SEM (defueling) active. My 24v (as well as any other 2nd gen 24v) is equipped with an unused j1939 bus, I am hoping to make it communicate with the Allison(I heard this can be done).
That said, the build ideas you both provided built up a lot of confidence in what I need. It's a littler overwhelming when most forums are talking about 500rwhp (and up) for drag racing and sled pulling. My needs are a reliable family tow rig for a 12,000-14,000 pound 5th wheel at 350rwhp, max. Likely it will only be 300rwhp, but I want to have some cushion.

Through my research I have heard of the Mike L parts. Is there a place that stocks the Mike L stuff, or should I call him at his shop. I see his number over at the Mike L transmission forum. Also Reybestos list the GPZ-1002 c2 as drop in, what is the reason for needing the alto apply Plate?

Part numbers For my future reference(it's easier to look here than to remember where I put them)
C1: Alto 152755
C2: Reybestos RGPZ-1002
C3: Alto 152757
C4: Alto 152758, or Stock
C5: Re-used

Also @THEFERMANATOR , @Rockabillyrat . Back when I did the rebuilds I did, I used Recon Converters, which is now trastar. Can I use one of their billet cover units, or should I go with DPC, or some other diesel specific performance converter?

Best Regards Guys!
 
No problem! The allison swaps I've done with a cummins so far where either P pumped or we did one 6.7. That was with the unreleased Suncoast kit that used a PCS to make everything talk. So I have not put the research into making a 24v properly command torque management on an Allison. But keeping it is a very good idea if you plan to use this truck to pull a significant sized camper/trailer. THEFERMANATOR is a communication wizard so he might have a better idea on that. I would imagine a PCS controller will be able to make it happen.

The allison is an easy rebuild. Actually was my first transmission to ever rebuild and I thought it was easy and straightforward.

I have no experience with the billet Recon/Transtar converters. We do alot of Suncoast converts with great success. I've been to their facility in Florida a few times for training and those guys make some top quality products.

Looking forward to seeing this build come together!
 
You can connect the j1939, but chances are it will not work with GM programming. J1939 is not all equal. GM used there own version with bidirectional control so that the TCM is what actually controls defuel. The ECM has a table that references a limiter for a torque value. The TCM adapts and varies/adjust the defuel amount by a torque table programmed into it. So just because you connect it, doesn't mean they can talk to each other. I'm sure you can find a calibration from Cummins that can work with defuel, and then go to Allison and find a medium duty file to work with it.

The transtar is a basic minor upgrade from stock, but cannot hold big power. A few have used single disc billet converters with great results with no pressure knockdown in lockup at 400hp with good success, but that's pushing it to its limit. ANY more and you better step up to a triple disc. Several have also used the LML, but it will be way to loose for a Cummins.

The C2 alto apply plate is because it's almost twice the thickness of stock and doesn't come with the raybestos pack. The raybestos pack uses a stock C2 steel plate as an apply which leaves you with apply pressure only on the outer edge of the clutches in a 5 speed leading to failure just like stock did. To run the alto plate you have to also switch out to thin instead of thick steels.

You would probably be best to call Evan at Limitless diesel about a kit rather than trying to piece together one. He will have everything in stock.
 
I don't have an alto 5 speed C2 apply plate, but this 6 speed plate should give you an idea of how it helps. On a 5 speed apply plate the thicker portion comes further in since the apply piston on a 5 speed only touches the inner edge, a 6 speed has centered apply. The stock C2 steel is .087 thick and is also used as the apply plate. The alto is .105 thick at the thin point, cllose to .200 thick at the thick portion, and is a harder material. 5 speeds had problems where only the inner half of the clutch would be worn due to the offset apply. The thicker plate helps to apply the whole clutch face.

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@THEFERMANATOR Thanks fore the additional information. I didn't figure the J1939 would be plug and play to a GM TCM. I was thinking more along the lines of a MD TCM, re-tuned for pickup quality shifting. I was going to contact Jason over at transmissiontunerdotcom. His web site claims he can make 2nd gen's with the J1939 bus connector talk to an allison, but I do not know what TCM or operating system he uses. I have a spare truck, so I may put the Allison in it to work on communications and tuning. That way I can keep driving my "driver" until I have something worked out. I actually don't mind the 47RE for casual everyday driving, but it turns into a mess when pushed hard, even with a DPC low stall converter. I know there is plenty more I can do with it, but it will never be the towing transmission the Allison is with the additional gear, and the much lower 1st gear, to get the load moving. Even if I had to run at 300rwp without SEM, I think I'd be farther ahead.
 
Not to hijack, but I am in a very similar situation. I have an allison 1000 5 speed 4x4 trans & an allison 2000 (with park pawl) 6 speed 2wd.

I just want a 6 speed 4x4 ally. Will I be able to just hijack the output shaft & tailshaft of the 4x4 trans? Not sure if it will work or not due to it being a 5 speed.
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Scholioso said:
Not to hijack, but I am in a very similar situation. I have an allison 1000 5 speed 4x4 trans & an allison 2000 (with park pawl) 6 speed 2wd.

I just want a 6 speed 4x4 ally. Will I be able to just hijack the output shaft & tailshaft of the 4x4 trans? Not sure if it will work or not due to it being a 5 speed.
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It's possible.
 
The September 2009 issue of Gears magazine shows how to repair a broke tailhousing without removing the transmission. I think the same procedure could be used to convert the 2000 to a 1000, and as Rockabilly said, the planetary also needs to be changed. The hole for the output shaft, through the p3 planet, is larger for the 34 spline shaft on the 2000 model.
 
I've done a lot of broken tailshaft housings with the trans still in the truck. Its not that hard if you take your time, but keeping everything in place as you go back together is a little bit if a challenge. Swapping out the rear planetary might be possible with with the transmission still in the truck.... only one way to find out.
 
The advice in the gears magazine, is to lift the rear of the vehicle higher than the front, using gravity to keep things in place.
 
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