Transmission missing 3rd?

[Flexia]

I have a 09 avalanche 4x4 and just had my truck tuned about a week ago. Im not sure if this is because of the tune or not but just started a couple days ago. It does it very intermittent and is hard to reproduce. Between gears the rpms shoot up. Seems to be mostly happening between 2nd and 3rd but has dont it between 1st and 3rd. Here is a quick video of the dash. Im close to calling the dealer but wanted to talk to my dyno shop that tunned it first but they are out till monday.

Here is a short video of the tach https://www.youtube.com/watch?v=gGDNOCtEh4E&feature=youtube_gdata_player

 

[southview]

my 08 2wd with 6.2 6speed does the same thing . It doesn't do it all the time but is very annoying. Have not found out or had anyone be able to tell what is the problem. My Tahoe has 118k miles and no codes

 

[southview]

so are we going to be looking at buying a trans soon. Anybody? We can't be the only ones with this problem