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Reply To: 2016 Sierra 8-Spd Issue

November 15, 2017 at 12:25 pm #180517
PissedOffGMowner
Participant

Good day to you all. I have a 2016 Sierra with the 8 speed transmission. At 18300 miles I took the local dealer because of a vibration at low RPM throughout the gear range; rough idle; and jerking gear changes from 1st to 2nd at low speeds.
The dealer had the truck for 5 days. They had to await the back-ordered tranny flush juice. They did the “triple flush” of the tranny and also replaced all 4 engine mounts. They claimed they updated the software on the truck engine management control and they also updated the software on the infotainment system.
I now have 19300 miles on the truck, and it is now going back for the exact same reasons – rough idle (not as bad as the first time), and the start of the vibrations.
I expect them to keep the truck for a week, as I dont wish to continue going back there every 6-8 weeks.
I was advised that they are short handed WRT transmission specialists. This is a common excuse in Fort Lauderdale, with at least 5 dealers all “sharing” the same transmission specialists.
My humble advise is to have them do the tranny flush and confirm there is a warranty on these services. I assume the flush is good for +- 1500 miles MAXIMUM.
As soon as I have my truck back, i shall report the dealers explanation.

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