10XL. Wiring harness to convert from a 4L70E transmission to a 4L80E transmission (Some 2006 On, 4L70E type with input speed sensor only . For 2007-2008 applications that have the input speed sensor built in to the transmission (15-pin connector). E38/T42 reprogramming required for proper operation.
This harness takes a black case connector, case side not wire side.
The computer must be re-programmed.
On 1997 back you will need a Compushift computer.