Stick it to The Man!.. named Allison... which is a girl’s name..?

Fision

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I need (ok:rolleyes:, really want) 6th gear unlocked on my tranny and need help.
I just purchased a 1996 IH 4900 with mechanically injected 250hp dt466 and Allison md3060. So far so good, right? EXCEPT—the Allison has the 6th gear locked out electronically :mad:. Apparently this is a pretty common “thing”; and I can live (with occasional resentment) with a 65mph top speed; but I’d rather not have to redline it in the process. I WANT MY DOUBLE O.D.!! It’s a software issue that requires Allison itself, Allison requires approval from the truck manufacturer (IH, in this case), and IH says “it’s too old, we don’t have records, blah, blah..” Various aftermarket gurus also say it’s too old for them to help with. I think it’s a WTEC II, with a lever shifter (which shows only 5 gears).
MY ideas: get a TCM (TCU? ECM? ECU? People seem to be using any/all these designations) from another rig that has the same/similar engine&tranny (anybody know of one?); OR get the numbers off such a transmission, bring my TCM into Allison as a “donor” to replace my (supposedly failed) 6 speed TCM, and have them reprogram it to the “OE” 6 speed spec (anybody willing to share some numbers?).
YOUR ideas?
Any knowledgeable, experienced help would be MUCH appreciated!
One last thing: I have only seen my truck in pictures! I live in Alaska, bought it online in the Cleveland Ohio area and will be picking it up Friday June 8 to drive back. 6th gear would sure be nice!
Side point: anybody know of sources of waste transformer fluid/ATF/oil on the route? I’m looking into setting up a mobile centrifuge/filter to cut down on fuel costs...
 

Fision

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Yup. A royal pain. The thread you posted is the most complete that I’ve run across. Also the longest. From what little I’ve learned about Allison’s (I’ve always owned stick-shifts) my best options are a new compatible TCM with the desired parameters or the numbers off such a tranny that I can take to Allison for reprogramming mine. Anybody out there..? Please:dunno
 

Thewespaul

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I have a 99 same truck just a dt466e, I’ll be following this thread closely. 65 mph top speed is brutal
 

Fision

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The link 79jasper sent has a lot of helpful info. I have an updated form from Allison and the form from IH that I’ll try and post as references for those who would like to try the official route. The feedback I got from IH is that they won’t approve anything older than about ‘04. That’s what they told ME, hopefully others will have a different experience. The rest of us rejects need a back door method.
 

Fision

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6th gear enabled!! 5/3/2019!
Having failed to locate a reasonably priced TCM with which to experiment, I took a gamble and had my TCM reprogrammed with the identity of a 6sp TCM that seemed a close match: one year age difference, same max rpm, both read rpm off a Throttle Position Sensor. The tech at Allison had to modify the programming slightly, but he was successful!
1hr flat rate- $140.
I supplied him with the photo of the 6sp TCM ID tag (I think what they needed was the CIN on the tag—the calibration number), my VIN, tranny serial number, and my TCM. I Also brought in my 5sp T-handle shifter so he could confirm compatibility; but I don’t think this is normally needed.
 

Fision

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Wow. I need this in my life, where did you take it?
To the local Allison dealer in Anchorage. The information requested by the Allison dealer is:
1) the CIN (Calibration Number?) from the 6sp setup. This number is on a sticker attached to the Transmission Control Module (TCM).
2) tranny serial # (yours!)
3) TCM part # (yours). Also found on a sticker on the TCM.
4) truck VIN (I thought they would need the VIN from the 6spd donor truck, which I didn’t know; so I gave them my VIN. No problem ).

With our older Internationals we have to supply Allison the CIN from a compatible 6spd to make it work. There seems to be no way International will ok it.

And as a side note Wes, you will like it! The 5-6 jump is much smaller (15%) than the 3-4 and 4-5 shifts. It’s just enough to drop rpm into a more comfortable range (or bump speed up) without bogging the engine.
 

Fision

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You must be registered for see images attach


This pic shows the TCM (which in this case is mated to a T-handle shifter, mine are divorced). Note the stickers with CIN and the part number.
Just to repeat: use the CIN with the 6spd programming, but the P/N of the actual TCM they will be reprogramming!
 

Fision

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Note the calibration parameters on the TCM stickers, . These are the things ones you’ll want to match up with your own (I.e.-model of transmission, gov rpm...)
 

Thewespaul

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Much appreciated, we’ve got a 2000 dt466e that’s all done at 62 mph. This ought to help out with some fuel savings this year
 

Fision

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A 2000 will be a WTEC3 control box. I think WTEC is an acronym for World Transmission Electronic Control, or something like that. You might contact Allison to check the compatibility of another generation WTEC programming with yours; they’re up to WTEC5 now. I needed WTEC2 because they use the old analog throttle inputs, though I’ve heard some of the WTEC3 did as well.
Again, all you need is the numbers off a compatible control box, not the unit itself.
 

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