Newell Gurus

On my Allison transmission control panel I have a Button labeled "Mode".  Right above the button I have a label "Perf".  So my question is....What is the button for and how do I use it?  I did a little research, and in general the Mode button changes the software settings in the transmission to choose different shift points.  The choice of the software changes are determined by the OEM manufacturer (Newell).

On my most recent trip, I experimented with the button.  I could not detect any specific change caused by the Perf button.  

Does anyone know what the button actually does?  

Cheers,
bill

I believe you are correct.  I researched it also and came to the same conclusion.  I can notice a huge difference in shift points under a load such as uphill.  Not so much on somewhat level ground.

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I'm going with 'Performance Mode':
I believe it makes the transmission shift a little earlier. It makes your coach feel like a 50,000 lbs Sports Car... well, sort of...