Eaton Autoshift/Ultrashift Transmission Harnesses
Replacing a manual transmission with an Eaton automated (Autoshift or Ultrashift) unit requires a complete electronic interface between the Transmission Control Module (TCM), Engine ECM, and chassis electronics. Without the proper harnesses, the shifter, dash indicators, and safety systems will not operate.
Kustom Truck Parts offers high-quality Eaton Ultrashift transmission harnesses and Eaton Autoshift transmission harnesses specifically engineered for Kenworth and Peterbilt trucks across multiple NAMUX generations.
Each complete kit includes the main transmission harness, ECA power harness, and dash interface harness (exact components vary by NAMUX generation). All harnesses are built with proper shielding, OEM-style connectors, and high-grade wiring for reliable J1939 communication and factory-like shifting performance.
Important: These kits are chassis-specific. For guaranteed compatibility, please provide the last 6 digits of your VIN when ordering.
Browse our Eaton Autoshift & Ultrashift transmission harnesses below to select the correct kit for your truck. Need help identifying your NAMUX generation? Contact our technical team — we’ll verify the right harness for your transmission swap!
