2018 GMC Sierra 1500 6L80

Complaint: Vibration after rebuild

Cause: one of the pump rotor veins was missing

Correction: install the missing pump vein

Part numbers related to the repair: NA

Year Make and Model of the Vehicle: 2018 GMC Sierra 1500

Mileage: 98,000

Transmission: 6L80E

Additional Notes: After rebuilding, the vehicle had a vibration that started at about 20mph that felt like a torque converter issue. The transmission was pulled back out and the replacement converter was changed again, however, it still had vibration. They pulled the unit again and when pump was taken apart the tech saw that 1 of the veins was missing as shown in the photos below. This was causing the converter or pump rotor to rotate possibly pushing them off-center. When the transmission was reinstalled and road tested the vibration was gone, the problem was a technician error.

Pictures/Diagram: Included below,

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