Holley Terminator X Max 6L80e 6L90e Transmission Controller GM 558-499


Out of stock till august 2023


****For use with Terminator X MAX ECU's, requires Terminator X V3 Build 100 or later firmware!

Part number: 558-499

Add GM 6L80/90E transmission control to any existing vehicle utilizing a Terminator X Max ECU. A departure from traditional Holley EFI transmission control, the Terminator X Max ECU allows the ability to use 2007+ GM 6L80E and 6L90E transmissions by communicating via CAN with the internal TCM (Transmission Control Module). The supplied Holley EFI OBDII Transmission Tuning Handheld is used to adjust Shift Points, Tire Size and Gear Ratio. The Terminator X V3 Software provides the ability to dial in Torque Management to optimize the desired shifting characteristics when using a 6L80/90E Transmission. Terminator X V3 software also allows a user to control the Secondary Shift Mode within the Transmission TCM and allows use of Tap Up/Down Shifting. Within Terminator X V3 PC Software o Virtual Torque Management Tables o Virtual TPS Tables to dial in shift characteristics regardless of engine o DBW and Timing torque reduction tables to create smooth shifts Within the Holley EFI OBDII Transmission Tuning Handheld o Ability to read and clear TCM fault codes o Ability to raise and lower shift points by MPH or RPM Support for Tap Up/Tap Down & Transmission's Secondary Shift Mode If you currently have a Terminator X ECU upgrading to a Terminator X Max ECU can be easily done by plugging your main harness into the Max ECU and re uploading your existing calibration


  • Included TCM handheld tuner with integrated wizard is required for setup in conjunction with the Terminator X 3.5” Handheld. Terminator X V3 software to unlocks optional tuning parameters.
  • Plug and play with any engine controlled by a Terminator X Max ECU
  • Supports - Shift Mode - Tap Up / Tap Down, and Torque Management
  • Four loose wires:
  • - Power (Red) – Supplies power to the transmission solenoids. This should be connected directly to the battery, or a constant battery source capable of supplying 5 amps
  • - Ground (Black) – Connect to a good chassis/engine ground source
  • - Brake Switch (Light Blue/White) – Wired to the brake light switch. This must be installed to a +12v source (as most brake light switches are)
  • - Park/Neutral Safety (Yellow) – Circuit for starter solenoid. When the transmission is in Park or Neutral this Yellow Wire will be Grounded (-). When the transmission is in gear this circuit will be open.