Hyundai Sonata 2015–2018 — technical service bulletin
Bulletin 21-AT-014H · NHTSA communication 10201469 · issued Aug 19, 2021
Technical service bulletin
communication type
Power Train
component
2015–2018
model years
7
vehicle entries
Official summary
Certain vehicles (listed below) equipped with 7-speed Double Clutch Transmissions (DCT) may exhibit abnormal vibration at low speeds. This bulletin outlines the procedures for diagnosing clutch judder, updating the Transmission Control Unit (TCU) with revised logic, and/or replacing the Double Clutch.
Vehicles covered
What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.