Jeep Grand Cherokee 2015 — technical service bulletin
Bulletin 21-039-14 · NHTSA communication 10139858 · issued Nov 25, 2014
Technical service bulletin
communication type
Power Train
component
2015
model years
1
vehicle entries
Official summary
Flash: Transmission Shift Enhancements This bulletin involves reprogramming of the Transmission Control Module (TCM) with the latest available software. The following TCM calibration improvements are available for vehicles equipped with the 845RE 8 speed transmission (sales code DFL) or 8HP70 8 speed transmission (sales code DFD or DFK). These improvements are listed per engine application.3.0L gas engine (sales code EHD) Improved upshift timing. Improved torque converter engagement. Improved shift timing during tow mode operation. Improved shift points during aggressive driving. Calibration i
Vehicles covered
What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.