Expanding on our Transmission Control options from Holley EFI. This new harness 558-455 from Holley EFI provides plug and play transmission control for the 2009+ GM 4L60 when used with a Dominator ECU. The 2009+ GM 4L60E contains an internal turbine speed sensor, which was not on the previous model year transmissions. Additionally, the valve body range selector is wired and controlled differently from the ECU.
- Built in Relay - Must be wired to a switched 12v source.
- Plug and play with 2009+ GM 4L60E Transmissions