Warranty

Hillsborough Transmission Limited Warranty

  • Coverage: Hillsborough Transmission warrants our rebuilt transmissions to be free from defects in materials and workmanship for a period of 3 Years or 36,000 Miles (whichever occurs first) from the date of invoice.

  • Installation Requirements: To activate this warranty, the following procedures MUST be strictly followed and documented:

  • Pre-Install Diagnostic Scan: A full system global scan (Engine, Transmission, ABS, Body Control, etc.) must be performed using a bi-directional diagnostic scan tool before installation. Active Engine/ABS codes that affect transmission operation must be repaired. The pre-scan report must be saved for warranty registration.

  • Torque Converter Seating: The transmission ships with the torque converter pre-seated and secured by a metal keeper (retaining bracket). Under no circumstances should the torque converter be removed from the transmission. The metal keeper is to be removed only during final installation. Removing the torque converter from the input shaft immediately voids the warranty due to the high risk of pump rotor damage during re-seating.

  • Cooling System: The transmission cooler lines and heat exchanger MUST be completely hot-flushed or entirely replaced prior to installation. Failure to remove debris from the previous transmission failure will contaminate the new unit and immediately void the warranty.

  • Post-Install Relearn: A bi-directional scanner must be used to clear old adaptive shift values and complete the "GM Adaptive Fast Learn" procedure. A final post-scan must be saved showing no active codes.

  • Fluid Requirements: Only OEM-approved full-synthetic transmission fluid may be used.

  • Exclusions: This warranty does not cover failures caused by:

  • Improper installation, incorrect fluid levels, or running the unit without fluid.

  • Shattered pump rotors resulting from improper bellhousing installation.

  • Abuse, neglect, racing, or commercial towing exceeding the vehicle manufacturer's original GVWR.

  • Accidents, water damage, or unauthorized modifications (including aftermarket TCM tuning not approved by Hillsborough Transmission).

  • Claims Process: In the event of a suspected failure, the customer must contact Hillsborough Transmission for diagnostics prior to any removal or repair. Unauthorized removal or disassembly of the unit voids this warranty.

  • Limitations: This warranty covers the physical transmission assembly only. It does not cover external labor for removal and reinstallation, towing expenses, loss of income, or rental car fees.