5.6

fairly significant
Crashes / Fires:
0 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
15,917 miles

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problem #3

Feb 072017

Sierra 3500

  • 150 miles
The vehicle will not shift properly when towing a trailer. While going up a hill, the transmission will not downshift properly. While going downhill, the vehicle downshifts to 2nd gear while going 60 mph. I have contacted GM several times (they have it on file) that there is a problem with the transmission. They understand but said that they cannot do anything about it. This has been happening since it was brand new. Over and over again.

- Hannacroix, NY, USA

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problem #2

Feb 202014

Sierra 3500

  • 31,200 miles
While driving on highway, transmission shifts hard to higher gear. This started all of a sudden will take to dealership.

- Edgewood, NM, USA

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problem #1

May 162013

Sierra 3500

  • 16,400 miles
While pulling my fifth wheel trailer 12500# at highway speed 65 mph pulling a grade the check engine light came on and the reduced engine power message appeared on the dash. This reduced and limited the speed to 50 mph and steps the truck down from there until you can only do 20 mph on the interstate. This issue has happened three times in three months.

- Wyoming , NY, USA

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