This service bulletin provides a Diagnostic Tip for Noise, Vibration, and/or Harshness Issues/Clunk Noise...
Chevrolet technical service bulletin 21-NA-120 for 2020-2025 Chevrolet Silverado 2500, 2020-2024 GMC Sierra 2500 and 2020-2024 Chevrolet Silverado 3500 and others.
- Bulletin number
- 21-NA-120
- Component
- Power train
- Summary
- This service bulletin provides a Diagnostic Tip for Noise, Vibration, and/or Harshness Issues/Clunk Noise Heard During Coast Down Event after the transfer case was removed from the transmission and reinstalled during a recent repair.
Owners of these vehicles have filed 348 complaints in the transmission category.
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