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Upgrading Allison shifter/ECU

PowerstrokeNC

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Greensboro, NC
Anybody done this?
I have the opportunity to upgrade my truck from the dual display shift pad and ECU. This is the one which shows number of gears available and what gear you are actually in. To the 'newer' one which only has one digital readout showing you how many gears are available.
The old ones display is green and kinda hard to read, the new one is red and letters are much thicker/bigger.
Can I just plug and play the upgrade along with the ECU that's behind the dash panel?

thanks for the help/comments.
 

Suprman

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Its not a plug and play swap. You would need a complete dash harness swap. The wtec3 ecu goes under the passenger dash. The harness going thru the cab out is different. The dash harness in a first gen truck is part of the relay breaker panel. I have taken apart the wtec2 keypad and used plastic polish to clean up the display plastic screen.
 

DiverDarrell

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I think also the internal electronic wiring of the transmission is different as well.

TM 9-2320-365-20-5

transmission/transmission controls adaptability chart.
 

Oxyacetylene

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I think also the internal electronic wiring of the transmission is different as well.

TM 9-2320-365-20-5

transmission/transmission controls adaptability chart.
I seem to remember some discussion about this and how they may have used some transmissions wired for WTEC3 with the WTEC2 controllers by modifying the wiring harness?
 

PowerstrokeNC

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Location
Greensboro, NC
Thanks for all the input. To add more details, I have a truck that has been converted and was thinking of swapping over the newer hardware to my other truck which is more of a 'daily driver' since I figured the newer version is probably better. Does anyone know if the software/hardware is better? Worth the work?
 

Suprman

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The wtec3 is more sensitive to wiring harness connections and will throw error codes and halt where the wtec2 is a bit lower tech and more forgiving. I believe the wtec3 has more options to change parameters and has the newer style diag/interface connection. Wtec3 parts are easier to get the wtec2 stuff is all out of production.
 

coachgeo

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North of Cincy OH
Thanks for all the input. To add more details, I have a truck that has been converted and was thinking of swapping over the newer hardware to my other truck which is more of a 'daily driver' since I figured the newer version is probably better. Does anyone know if the software/hardware is better? Worth the work?
Will there be a time that Wtec II set up transmissions will no longer be available? If you folk think so...... IMHO help Powerstrock do the conversion, but not for the reasons mentioned but to discover better the steps and all the components needed to do it.

Document everything. Help him backward engineer everything and do write ups on how to make up a copy of the kit. That way all the members here will have the knowledge and can build up the parts allowing all of us the opportunity in future to use WtecIII setup trannies when the WtechII supply runs out????

Granted I think the only differences are electronic/software.

Talked to an an Allison re-builder/seller who said the components to go from one to the other from Allison would be about $4,000. Then again if your say swapping in a WtechIII tranny into an older Truck wouldn't some of those components come with the Tranny? (ECU etc.)
 
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PowerstrokeNC

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Location
Greensboro, NC
I am going to open the dash up on both trucks so that I can verify all the connections/changes.
Since I have both versions side by side it will be easy to compare (I will take pics)
I did notice on the converted truck they also changed connectors to other items behind the dash like the idiot lights for example.
Not sure if that was due to trans changeover yet or not.
Will report back findings
 
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tobyS

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Are they both first gen trucks? A1 trucks have different wiring harnesses and dash instrumentation to begin with.
Wow Will, I know you like them, but the SS FMTV sounds like a pain in the as$. Are they made in America? I went for simplicity and got 2 M35A3's.
 

Suprman

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Its not a pain for me. If you want to do swaps and upgrades it can be. The 4x4 lmtv could
drag the 6x6 deuce down the street backwards kickin n screamin though.
 

Suprman

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I think the first gen trucks that have wtec3 were upgraded at some type of rebuild. I have taken a few apart they dont look like the dash was taken apart and harnesses replaced at unit level.
 

tobyS

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Its not a pain for me. If you want to do swaps and upgrades it can be. The 4x4 lmtv could
drag the 6x6 deuce down the street backwards kickin n screamin though.
LOL....probably.

I imagine with some experience they grow on you. It sounds like the electrical issues are as much of an issue as the A3's tranny, but you seem to have overcome them! You've certainly become an expert! Have a great day.
 

Overdrive

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I believe the swap from II to III is covered in TM 9-2320-365-20-3 (A0 trucks), 8-8. WTEC III TRANSMISSION CONTROLS INITIAL INSTALLATION, page 662 paragraph 8-26.
 
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