21-017-16

Flash: Transmission Shift And Drivability Enhancements This bulletin involves reprogramming the Transmission Control Module (TCM) with the latest available software. Some customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation, a technician may find the following Diagnostic Trouble Code (DTC) stored in the TCM memory: · P0731 - Gear Ratio Error In 1st. The following enhancements are included in the software update: · Improved general shift quality. · Improved 7th gear upshift timing. · Downhill engine braking improvements.