P0734 on the 2015 Dodge Durango
The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.
Nobody has written a description of this code yet.
| 21-027-15 REV. C | 2022-08-08. Service bulletin. Flash: Transmission Shift Enhancements This bulletin involves reprogramming of the Transmission Control Module (TCM) with the latest available software. A small number of customers may experience an erroneous Malfunction Indicator Lamp (MIL) Illumination. Upon further investigation, the technician may find a Diagnostic Trouble Code (DTC) stored in the TCM memory. In addition, the following TCM calibration improvements are also available for vehicles equipped with the 845RE 8 speed transmission (Sales Code DFL). These improvements are listed per engine application. 3.0L Gas Engine (Sales Code EHD) ? P1DCD - TCM monitoring processor performance multiple clutches locked up. ? P1B13 - Park-By-Wire unintended out of park position. ? P0734 - Gear 4 Shift Incorrect Ratio. ? Improved upshift timing. ? Improved torque converter engagement. ? Improved shift timing during tow mode operation. ? Improved shift points during aggressive driving. ? Calibration improvement to correct bump feel during 2-1 downshift. ? Improved shift timing while in snow, base, and hill modes. 3.6L Gas Engine (Sales Code ERB) ? P1DCD - TCM monitoring processor performance multiple clutches locked up. ? P1B13 - Park-By-Wire unintended out of park position. ? P0734 - Gear 4 Shift Incorrect Ratio. ? Improved 4-3 and 3-2 downshifts. ? Improved shift timing at higher altitudes. ? Improved shift timing while in sand mode. ? Calibration improvement for multi-gear downshift timing during passing maneuvers. ? Calibration improvement for intermittent delayed upshift. |
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| 21-027-15 REV. C | 2022-07-25. Service bulletin. Flash: Transmission Shift Enhancements This bulletin involves reprogramming of the Transmission Control Module (TCM) with the latest available software. A small number of customers may experience an erroneous Malfunction Indicator Lamp (MIL) Illumination. Upon further investigation, the technician may find a Diagnostic Trouble Code (DTC) stored in the TCM memory. In addition, the following TCM calibration improvements are also available for vehicles equipped with the 845RE 8 speed transmission (Sales Code DFL). These improvements are listed per engine application. 3.0L Gas Engine (Sales Code EHD) ? P1DCD - TCM monitoring processor performance multiple clutches locked up. ? P1B13 - Park-By-Wire unintended out of park position. ? P0734 - Gear 4 Shift Incorrect Ratio. ? Improved upshift timing. ? Improved torque converter engagement. ? Improved shift timing during tow mode operation. ? Improved shift points during aggressive driving. ? Calibration improvement to correct bump feel during 2-1 downshift. ? Improved shift timing while in snow, base, and hill modes. 3.6L Gas Engine (Sales Code ERB) ? P1DCD - TCM monitoring processor performance multiple clutches locked up. ? P1B13 - Park-By-Wire unintended out of park position. ? P0734 - Gear 4 Shift Incorrect Ratio. ? Improved 4-3 and 3-2 downshifts. ? Improved shift timing at higher altitudes. ? Improved shift timing while in sand mode. ? Calibration improvement for multi-gear downshift timing during passing maneuvers. ? Calibration improvement for intermittent delayed upshift. |
| 21-027-15 REV-C | 2018-12-17. Service bulletin. Flash: Transmission Shift Enhancements This bulletin involves reprogramming of the Transmission Control Module (TCM) with the latest available software. A small number of customers may experience an erroneous Malfunction Indicator Lamp (MIL) Illumination. Upon further investigation, the technician may find a Diagnostic Trouble Code (DTC) stored in the TCM memory. In addition, the following TCM calibration improvements are also available for vehicles equipped with the 845RE 8 speed transmission (Sales Code DFL). These improvements are listed per engine application. 3.0L Gas Engine (Sales Code EHD) ? P1DCD - TCM monitoring processor performance multiple clutches locked up. ? P1B13 - Park-By-Wire unintended out of park position. ? P0734 - Gear 4 Shift Incorrect Ratio. ? Improved upshift timing. ? Improved torque converter engagement. ? Improved shift timing during tow mode operation. ? Improved shift points during aggressive driving. ? Calibration improvement to correct bump feel during 2-1 downshift. ? Improved shift timing while in snow, base, and hill modes. 3.6L Gas Engine (Sales Code ERB) ? P1DCD - TCM monitoring processor performance multiple clutches locked up. ? P1B13 - Park-By-Wire unintended out of park position. ? P0734 - Gear 4 Shift Incorrect Ratio. ? Improved 4-3 and 3-2 downshifts. ? Improved shift timing at higher altitudes. ? Improved shift timing while in sand mode. ? Calibration improvement for multi-gear downshift timing during passing maneuvers. ? Calibration improvement for intermittent delayed upshift. |
| 21-027-15 | 2018-12-10. Service bulletin. Flash: Transmission Shift Enhancements This bulletin involves reprogramming of the Transmission Control Module (TCM) with the latest available software. A small number of customers may experience a Malfunction Indicator Lamp (MIL) Illumination. Upon further investigation, the technician may find Diagnostic Trouble Code (DTC) P0734 - Gear 4 Shift Incorrect Ratio stored in the TCM memory. In addition, the following TCM calibration improvements are also available for vehicles equipped with the 845RE 8 speed transmission (sales code DFL). 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 improvement to correct bump feel during 2-1 downshift. ? Improved shift timing while in snow, base, and hill modes. 3.6L gas engine (sales code ERB) ? Improved 4-3 and 3-2 downshifts. ? Improved shift timing at higher altitudes. ? Improved shift timing while in sand mode. ? Calibration improvement for multi-gear downshift timing during passing maneuvers. ? Calibration improvement for intermittent delayed upshift. |
| 21-027-15 REV-B | 2018-11-26. Service bulletin. Flash: Transmission Shift Enhancements This bulletin involves reprogramming of the Transmission Control Module (TCM) with the latest available software. A small number of customers may experience an erroneous Malfunction Indicator Lamp (MIL) Illumination. Upon further investigation, the technician may find a Diagnostic Trouble Code (DTC) stored in the TCM memory. In addition, the following TCM calibration improvements are also available for vehicles equipped with the 845RE 8 speed transmission (Sales Code DFL). These improvements are listed per engine application. 3.0L Gas Engine (Sales Code EHD) ? P1DCD - TCM monitoring processor performance multiple clutches locked up. ? P1B13 - Park-By-Wire unintended out of park position. ? P0734 - Gear 4 Shift Incorrect Ratio. ? Improved upshift timing. ? Improved torque converter engagement. ? Improved shift timing during tow mode operation. ? Improved shift points during aggressive driving. ? Calibration improvement to correct bump feel during 2-1 downshift. ? Improved shift timing while in snow, base, and hill modes. 3.6L Gas Engine (Sales Code ERB) ? P1DCD - TCM monitoring processor performance multiple clutches locked up. ? P1B13 - Park-By-Wire unintended out of park position. ? P0734 - Gear 4 Shift Incorrect Ratio. ? Improved 4-3 and 3-2 downshifts. ? Improved shift timing at higher altitudes. ? Improved shift timing while in sand mode. ? Calibration improvement for multi-gear downshift timing during passing maneuvers. ? Calibration improvement for intermittent delayed upshift. |
| 21-027-15 REV-A | 2018-11-26. Service bulletin. Flash: Transmission Shift Enhancements This bulletin involves reprogramming of the Transmission Control Module (TCM) with the latest available software. A small number of customers may experience an erroneous Malfunction Indicator Lamp (MIL) Illumination. Upon further investigation, the technician may find a Diagnostic Trouble Code (DTC) stored in the TCM memory. In addition, the following TCM calibration improvements are also available for vehicles equipped with the 845RE 8 speed transmission (Sales Code DFL). These improvements are listed per engine application. 3.0L Gas Engine (Sales Code EHD) ? P1DCD - TCM monitoring processor performance multiple clutches locked up. ? P1B13 - Park-By-Wire unintended out of park position. ? P0734 - Gear 4 Shift Incorrect Ratio ? Improved upshift timing. ? Improved torque converter engagement. ? Improved shift timing during tow mode operation. ? Improved shift points during aggressive driving. ? Calibration improvement to correct bump feel during 2-1 downshift. ? Improved shift timing while in snow, base, and hill modes. 3.6L Gas Engine (Sales Code ERB) ? P1DCD - TCM monitoring processor performance multiple clutches locked up. ? P1B13 - Park-By-Wire unintended out of park position. ? P0734 - Gear 4 Shift Incorrect Ratio ? Improved 4-3 and 3-2 downshifts. ? Improved shift timing at higher altitudes. ? Improved shift timing while in sand mode. ? Calibration improvement for multi-gear downshift timing during passing maneuvers. ? Calibration improvement for intermittent delayed upshift. |
6 on file from NHTSA, as of 2026-10-19. See them in the bulletin list. A bulletin lists model years: read the document for which vehicles it concerns.