Holley EFI Transmission Control Harness - GM 4L60 (Pre-2009) and 4L80 All and a 12 percent thicker

and a 12 percent thicker core area with a major increase in volume

Rear springs The factory springs are swapped out in favor of a full replacement Glideride leaf pack designed for great on/off-road performance

particularly big cams that tend to reduce low-end power and torque

2003 2500/3500 Cummins Dodge

Holley EFI Transmission Control Harness - GM 4L60 (Pre-2009) and 4L80 All and a 12 percent thickerExpanding our transmission control options for our EFI systems, this harness provides plug and play for Pre 2009 GM 4L60 and 4L80 transmissions using a Dominator. This also contains a J4 connector to operate GM electronic transmissions.