LLY: 2004 LLY Allison Issues, please help!

K

ksstang

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May 17, 2011
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I just know the 1-2 shift is harder than normal, same with 2-3, then the 3-4 and 4-5 shift happens super fast and its usually in overdrive by 30mph. It keeps throwing a U100 loss of communication with ECM/TCM code. This all happened overnight one night. It was fine one night, and got in it the next afternoon and noticed all this weird stuff going on.
 
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Mike L.

Mike L.

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You may have a problem with the transfer case control module. The TCM might think the T/C is in 4 wheel low.
 

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ksstang

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May 17, 2011
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Mike, could that be causing the loss of communication codes? And where exactly is that control module at? I'm having a hard time figuring that out by the picture.

Thanks!
 
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ksstang

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May 17, 2011
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Lawrence, KS
Well, I think this is the final update! Went ahead and changed out the glow plug module which was throwing the code. No matter what I did after clearing that code, the glow plug module code would pop right back on. Ordered a new module from Napa and installed today. Got the snap on solus out, reset the code and it has yet to come back. Drove the truck off and on all evening, getting it up to operating temp and everything seems normal. So, I'm wondering if something was shorted out inside that module, causing backed through it causing all the loss of communication crap. Needless to say, if this for sure fixes it I'm baffled!
 
Awenta

Awenta

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All the modules communicate in order so it is possible that it was causing noise further down the line.

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awb061196

awb061196

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Is it ok to run efi live with a bully dog.. If I'm just running my bully dog for the Gauges it's set on stock??


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Awenta

Awenta

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Why would you post that in this thread?

I believe you can but I never used one so I don't know for sure.

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