2012 GMC Sierra Shifting

[2012gmc]

Good day,

 

I have a 2012 GMC Sierra 1500 Z71 4x4 SLT.  Latley I have had an issues with the shifting.  Most of the time all is good, but when I'm going between 35 and 40 and let off the gas then give it some gas it hits real hard.  It does the some what of the same when I am on the highway going about 70 and I give it more gas. On the highway it seems to down shift ( feels like I'm stopping) than shifts hard.  The transmission was just rebuilt and I just replaced the tps and cleaned the throttle body. I at a loss and am running out of money to throw at it. The transmission shop ensures me it is not the shift soleniods, he says if it was I would have a lot more shifting issues than I currently have. Also, the check engine light does not come on and there are no codes in the history. Any help would be appreciated 

Edited October 3, 2018 by 2012gmc

[Blake2020]

Same issue happening for 2 years . 2012 GMC Sierra. Found the solution?