21-003-14 REV. A

Flash: 845RE Transmission Shift Enhancements, 2-1 Downshift This bulletin involves reprogramming the Transmission Control Module (TCM) with the latest available software. The following TCM calibration improvements are available for vehicles equipped an 845RE Automatic Transmission (Sales Code DFL). These updates are listed by vehicle and engine.LD and LX vehicles equipped with a 3.6L engine (Sales Code ERB) Software to correct a harsh bump feel during a 2-1 downshift. Software to enable the scan tool based transmission ?Quick Learn.? Software to address customer concerns of Malfunction Indicator Lamp (MIL) illumination and Diagnostic Trouble Code (DTC) P215C Output Shaft Speed, Wheel Speed Correlation setting on AWD equipped vehicles.LX and WK vehicles equipped with a 3.0L engine (Sales Code EHD) Software to correct a harsh bump feel during a 2-1 downshift.WK vehicles equipped with a 3.6L engine (Sales Code ERB) Software to correct a harsh bump feel during a 2-1 downshift.DS vehicles equipped with 3.6L engine (Sales Code ERB) Software to correct a harsh bump feel during a 2-1 downshift. Software to address a customer?s concern of less than desired shift quality in Four Wheel Drive (4wd) Low mode during medium to heavy acceleration. Software to address customer concerns of Malfunction Indicator Lamp (MIL) illumination and Diagnostic Trouble Code (DTC) P215C Output Shaft Speed, Wheel Speed Correlation setting on AWD equipped vehicles. Software improvements to powertrain braking in Tow/Haul mode. Software to improve downshift response from a medium to heavy pedal acceleration. Driveability improvements at higher altitudes. Software to improve acceleration during cruise control operation Software to correct a condition where DTC U11C3 - ESM Lost Communication With TCM On D-Pt CAN may have been displayed instead of U11E3 - TCM Lost communication with ESM On D-PT CAN.WD vehicles equipped with a 3.6L engine (Sales Code ERB)