After you're done with the engine tune, it should show transmission tunes. Stock, Firm, and Hard. And then options for customizing them. At least that's how mine is....
If yours isn't showing the trans options, maybe try updating again?

I received my Intune yesterday, ran the updates and installed the 87 octane tune on my 08 Sierra 5.3l. I just wanted to tell you guys how happy I am with it so far. It's a very noticeable improvement! Better throttle response, more power, and the trans shifts great on the firm setting. And no more ...

Thanks! I've ordered one!

I'm probably going to be ordering an Intune for my 2008 Sierra in the next while, and I just have a quick question first. My truck has the 5.3l Flex Fuel engine. Is the Intune compatible with the Flex Fuel? Can I still fill up with E85 on occasion?
Thanks!