Is this something that can be adjusted manually? Or do you need to access and 'reprogram' the computer?

Edit:

I have been doing a lot of reading and it seems the idle is computer controlled - as I suspected.

I was looking to adjust the idle myself because I (like many) have the dreaded idle vibration and changing the idle speed depending on the season is helpful. I am just tire of taking it to the dealer to get it adjusted.

As a side note.

I dont think the idle vibration is coming from the engine. Instead, I suspect it is the transmission itself that is causing the stoplight vibrations.

BTW, does the 3.0 use the same auto tranny as the 4.4?