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View Full Version : 'Hot Transmission' mode shifts



rocks2005
August 15th, 2009, 03:53 AM
I was looking at the tuning for my 5 speed Allison and there are different patterns:

Pattern A = Normal mode shifts
Pattern B = 4wd Lo mode shifts
Pattern C = Hot Transmission mode shifts
Pattern D = Tow/Haul mode shifts

I understand what Patterns A, B, & D are talking about but I’m in the dark about Pattern C = Hot Transmission? Can anyone help me out? I can find any information on what parameters cause the transmission to go into the this shift mode.


Thanks

Rick

2001 Duramax 4x4
Efi Live
BD Flow Max Lift Pump
50% over injectors from Diesel Injection
ATS Build Allison
AFE air intake

Big Mike
August 15th, 2009, 05:12 AM
The shift points, shift characteristics and TTC control are modified when the trans detects that it's running in an overheat condition (too hot) in an effort to control or reduce heat buildup. There's no visible settings or adjustments in EFI Live that I'm aware of that determine exactly when it will go into this mode, you can only change the charactoristics of the mode once it's there. but IIRC for the Allisons it's aprox 270*-300F* which IMO is way too late.

When making adjustments to the "normal" settings I normally also make the settings the same in the "hot" mode also, as sometimes the adjustments don't work unless they're changed across the tables.

And I don't depend on "hot mode" to protect the trans anyway...thats the operators job. :good: