18-040-17 REV. A

Flash: 6.4L Powertrain Diagnostic and System Enhancements This bulletin involves reprogramming the Powertrain Control Module (PCM) with the latest available software. This bulletin fixes all vehicles listed and also contains an optional software path for situations where the customer is specifically complaining of a drone noise, shudder, pulsation, or vibration under light throttle applications, while vehicle is operating in Multi Displacement System/Economics (MDS/ECO)mode (optional software available for D2&DJ vehicles).There will be two separate software options displayed on the wiTECH flash tab. The software file released for this condition contains the verbiage MDS NOISE. The other file is the standard software that does not contain improvements for the drone/shudder concern. If for some reason the customer finds this shudderimprovement objectionable, the PCM software may be returned/reflashed to the standard version.Both software versions will address the remaining conditions noted in the bulletin.A small number of customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find that the following DTCs have been set:P1404 - EGR Close Position Performance. P0404 - EGR Position Sensor Performance. P0405 - EGR Position Sensor Circuit Low. P0406 - EGR Position Sensor Circuit High. P2172 ? High Airflow/Vacuum leak detected. P0870 - OD Hydraulic Pressure Test (66RFE Only). This software update also includes the following enhancements:Reduced downhill gear hunting when using cruise control. Reduced drone noise at minimum converter clutch operating speed. Reduced low speed drone noise. Improved Exhaust Gas Recirculation (EGR) valve control at maximum desired lift. This will help reduce, long crank/start time. Improvements to engine idle quality such as rough idle after high altitude start and stability of engine RPM at idle. Refine MDS transitions with improved slip and torque management