Jeep Wrangler 2014–2015 — technical service bulletin
Bulletin 21-026-15 · NHTSA communication 10150549 · issued Apr 21, 2015
Technical service bulletin
communication type
Power Train
component
2014–2015
model years
2
vehicle entries
Official summary
Flash: Transmission Shift And Drivability Enhancements This bulletin involves reprogramming the Transmission Control Module (TCM) with the latest available software. A small number of customers may experience one or more of the following transmission related concerns. ? Less than desired shift response when towing or driving up steep hills in high ambient temperatures. ? Delayed shift when driving in 4WD Low. ? Vibration or resonance in the cabin on acceleration from a cruising speed.
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.