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Reply To: 2016 Sierra Shifting Problem 6 speeed automatic

March 12, 2019 at 4:17 pm #530038
DazzRozze
Participant

Hi,
I have a 2014 GMC Denali and have had exactly the same problem you’ve are talking about.. Yesterday I put my Vehicle in to have it checked out at the Australian dealership for GMC. They did updates on the PCM, GLO Plug module and TCM as I kept on getting Code P2202 which involved the Nox circuit.
Next they did a software update on the Transmission and fixed the Clunky problem. It now changes as smooth as and could not be happier with the result.
The people I took it too were Performax Australia in Northlakes Qld.

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