ATSG CONFIRMED FIX - NOVEMBER 2022
2017 Chevy Silverado 1500 6.2L 8L90
Complaint: After rebuilding, transmission has a tie-up on a 7-6 with harsh downshift and setting code PO747, ss1 stuck on, 1-2-7-8-R not released, and going into failsafe.
Cause: The 1-2-7-8-R clutch return spring which is a Bellville Spring was installed upside down.
Correction: Assemble the spring in correct direction which is dish side down.
Part numbers related to the repair: NA
Year Make and Model of the Vehicle: 2017 Chevy Silverado 1500 6.2L
Mileage: 90,545
Shop Name: Atec Transmission
Transmission: 8L90
Additional Notes: Vehicle only came to the shop with a torque converter shudder, new complaint was due to rebuilder error, with the Bellville spring being installed wrong this was causing too slow of a release for the 1-2-7-8-R clutch which was causing the tie-up and harsh downshift.
Pictures/Diagram: Included below. Pictures are of the clutch application and clutch spring being installed in the correct position.
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