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2015 Sierra LT All-Terrain Transmission getting stuck in 2nd and 3rd


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So up until yesterday the truck was driving relatively smoothly, there was the occasional hard shift from 1st to 2nd (which I believe these trucks are known for). I stopped at a stop light yesterday and started going and then at about 20 MPH the truck decided it didnt want to shift. This happened a few times throughout the day and seemed to get worse as the day went on and at this point it now does it every time it gets down into the lower gears. I switched to manual to see what gear it was stuck in and it showed 2nd and then 3rd after it shifted and didnt want to shift up. 

 

EDIT: Transmission temps when I was looking did not appear to get above 205 F, Fluid is red like it should be, level seems fine. 


Is there a known issue with these transmissions or an easy fix I can attempt? Transmissions are voodoo to me

Edited by GrootSquad
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