At wide open throttle, you can really feel the power drop while shifting. It lays down like a dog. Then it comes back at midrange power, until the next shift. This truck is stock with no tuner. I'm wondering if people that use tuners notice any difference or get the same thing? I can understand why it might be tuned this way, but we had a Duramax/Allison that never did this.

 

Mine doesn't do that. Power stays on strong till I back off the fuel.

 

Mine also stays strong as heck until you let off the go pedal.....sounds like you need to take it back to the dealer....

 

Goes better in manual shift mode. Keep rpms below 2800 and above 2000 during full throttle and she does nicely stock. I think I clocked an 8-9 second zero-60 time once.

 

Interesting point, I'll try that.

 

Mine really falls flat between shifts too. I came from programmed dmax's as well. Still wouldnt trade my Ford back for a GM.

 

Yep, if you can manually shift before the torque converter locks up, it's lots of fun.
After doing this a few times, you'll learn when to shift to keep it unlocked.
Keeping the RPMs in the range ruschejj mentions will give you a higher chance of the TC staying unlocked.
You can hit 21 PSI boost in 6th with around 2,200 RPMs this way.
Sometimes I miss it, the TC locks and the fun is over and all the power goes away with your foot to the floor.