LMM Allison 1000 shift options stand alone.

[Mogman]

On my LMM stand alone install I have 4 "drive" shift positions marked OD, D,2,1 if there is a 5th position I cannot shift to it. I am using the transmission shift detents for reference.
The OD and D position act the same, good all the way to 6th gear, the 2 and 1 position only give me 1st gear this is not what the owners manual says these should be.
What options if any do I have for ether re-programming the shifter or adding any external devices IE a tow switch or paddle shifter for manual operation in this stand alone application?
THANKS!!
Oh yes my trans temp gauge mounted in the cast aluminum pan indicates a fairly consistent 180-185 deg, does the Allison 1000 have a thermostat in the cooler circuit? It sure acts like it as my setup has a completely separate trans cooler with no radiator exchanger.

 

[PureHybrid]

First notch down from "D" in the trucks is for manual mode. Do you have a tap shifter?

 

[Mogman]

First notch down from "D" in the trucks is for manual mode. Do you have a tap shifter?

No I do not have a tap shifter, When the LMM came out they moved allot of what other modules were doing to the BCM for some reason, I think that the shift control switches were connected to the BCM, of course I hope I am wrong.

 

[Cougar281]

I'm not sure about the LMM, I'd have to dig out some schematics, but on the LBZ, the tap shift inputs go to the TCM.

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[Mogman]

I looked at the connector views on both the BCM and the TCM but could not find anything that looked like tap up or down, the cruse control and the tow/haul swich are on the BCM in the LMM.

 

[Cougar281]

Looks like they did move the tap up/tap down to the BCM on the LMM. Since you're running a standalone, I wonder if a LBZ TCM calibration would work?

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[Mogman]

Looks like they did move the tap up/tap down to the BCM on the LMM. Since you're running a standalone, I wonder if a LBZ TCM calibration would work?

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I think there is significant differences, for example on the LBZ the TCM tells the TCCM it is in neutral with a single wire signal, on the LMM it is conveyed via data on the high speed LAN. (this I learned from a small company making a complete stand alone TCCM setup)

I am thankful the transmission is working out as well as it is, would be nice to be able to lock it into one gear or another

 

[Chevy1925]

you can always throw a bcm back in down the road once you get everything else squared away and see if you can get it to play nice while giving tap shift.

 

[Mogman]

you can always throw a bcm back in down the road once you get everything else squared away and see if you can get it to play nice while giving tap shift.

Really is not enough room for the BCM, the dash area on the HMMWV is very small