When my 06 GT automatice is in the 40mph range and I am coasting for a bit then try to accelerate i hear loud rumbling under my seat and dont accelerate! The only way I get going again is if I WOT it. It literally takes me more then 10 seconds to go from 40mph to 50mph even if I push the pedal 3/4 to the floor.

The closer I get to operating temp the worse it gets.

Cleaned the MAF, TB, and reset the adaptive learning.

Tried 4 different tunes and non have solved this problem.

Anyone have this problem?

 

Did you reset the adaptive learning by disconnecting the battery for 30 minutes?

Also, see if recalibrating the gas pedal/TB helps:
-Turn the ignition to ON so the dashboard lights come on and the chime sounds(Do not start the engine).
-After the chime stops, smoothly depress the gas pedal to the floor while counting 1001-1002-1003.
-Smoothly release the gas pedal doing the same count.
-After the gas pedal is fully released, wait 6 seconds, then turn the ignition to OFF.
-Wait 6 more seconds, and repeat the procedure 2 more times.