2021-2023 Jeep Wrangler D Clutch Repair TSB

Owners of various 2021-2023 Stellantis vehicles, including the Jeep Wrangler, may encounter a Malfunction Indicator Lamp (MIL) illumination accompanied by specific Diagnostic Trouble Codes (DTCs) related to the transmission's D clutch. This issue is detailed in Technical Service Bulletin (TSB) 21-039-24 REV. F, which outlines the necessary repair procedure.

The TSB 21-039-24 REV. F, issued on October 16, 2024, supersedes TSB 21-039-24 REV. E, dated October 10, 2024. It applies to vehicles equipped with the Eight-Speed Auto 850RE Transmission (Sales Code DFT).

Symptoms

Owners will typically notice the Malfunction Indicator Lamp (MIL) illuminating on the dashboard. This warning light indicates a detected issue within the vehicle's systems. Alongside the MIL, specific Diagnostic Trouble Codes (DTCs) will be stored in the vehicle's computer, pointing to a problem with the transmission's D clutch. If your 2021-2023 Jeep Wrangler exhibits these symptoms, it's crucial to have it inspected.

Fault Codes / DTCs

This Technical Service Bulletin applies when the Malfunction Indicator Lamp (MIL) is illuminated and one or more of the following Diagnostic Trouble Codes (DTCs) are present:

• P0733-00 - Gear 3 Shift Incorrect Ratio
• P1DA8-00 - Incorrect Gear Ratio Clutch A B or D Defective
• P1D92-00 - Incorrect Gear Ratio - Clutch 4 Defective

Diagnosis / Trigger Conditions

The primary trigger for this TSB is the presence of the Malfunction Indicator Lamp (MIL) combined with any of the listed DTCs. If these conditions are met, the bulletin directs technicians to proceed with the D clutch repair. If these specific DTCs are not present, the bulletin does not apply to the vehicle's condition.

Repair Procedure Summary

The repair outlined in TSB 21-039-24 REV. F involves replacing the D clutch within the transmission. The procedure is extensive and requires careful disassembly and reassembly of transmission components. Here's a summary of the key steps:

1. Initial Checks: Verify the presence of DTCs P0733-00, P1DA8-00, or P1D92-00. If these codes are not present, the bulletin does not apply.
2. Transmission Disassembly: The process begins with removing the torque converter. For 4WD vehicles, the transmission housing extension is removed, followed by the output shaft seal and snap ring. For 2WD vehicles, the output shaft flange locknut staking is removed. The transmission oil pan and gasket are then removed.
3. Valve Body and Sensor Removal: The Hydraulic Impulse Oil Storage (H.I.S.) connector is disconnected, and the valve body assembly, Output Speed Sensor (OSS), and electrical harness insulator are carefully removed.
4. Internal Component Removal: Technicians proceed to remove the input shaft O-ring, oil pump housing, B clutch spring damper, and park pawl lock rod guide plate. The input/output shaft and P4 annulus drum assembly are then removed from the transmission case.
5. Clutch Disassembly: The P4 annulus drum assembly is positioned on a press fixture. The B clutch pack, P1 annulus/B clutch hub assembly, thrust bearing, and holding plate are removed. Special tools like Rings Support 10378 are used to protect the drum while prying the snap ring.
6. D Clutch Access: The P1 planetary carrier, input shaft with P2 planetary carrier, thrust bearing, washer, and P2 annulus/P3 sun gear are removed. Finally, the D clutch drum is removed from the P4 annulus drum. The P4 planetary carrier/output shaft lock ring is removed and discarded, as a new one will be installed during reassembly.
7. Reassembly: The reassembly process largely reverses the disassembly steps, installing new components where specified. This includes installing a new P4 planetary carrier/output shaft assembly, the D clutch drum, P2 annulus/P3 sun gear, input shaft, snap ring, thrust bearing, P1 annulus/B clutch hub, and the B clutch discs and plates. The park pawl lock rod, oil pump housing, and a new input shaft O-ring are reinstalled.
8. Final Assembly and Fluid: The Manual Park Release (MPR) lever is temporarily installed to release tension. Fluid transfer tube O-rings are replaced, and the valve body assembly, Output Speed Sensor, and H.I.S. are reinstalled. The transmission oil pan and a new output shaft seal are fitted. For 4x4 vehicles, the extension housing is installed; for 2WD, the output flange. The torque converter is reinstalled.
9. Post-Repair Procedures: Before installing the transmission back into the vehicle, it is pre-filled with the specified transmission fluid. After installation, a Quick Learn Procedure is performed using wiTECH, and any remaining DTCs are cleared.

Required Tools or Parts

Several specific parts and special tools are required for this D clutch repair:

• D Clutch Repair Kits:
  • 68676890AB (4x4 JL, JT, WD, WK)
  • 68676891AB (4x4 WL)
  • 68676887AB (4x4 DS, DT, DX, WS)
  • 68239499AD (AWD LA, LD, LX)
  • 68676892AB (RWD LA, LD, LX)
  • 68676894AB (RWD WD, WK)
  • 68676893AB (RWD DS, DT, DX, WS)
• Automatic Transmission Fluid: Part number 68218925AB (10 AR)
• Special Tools:
  • Guide Sleeve: 10377
  • Press Fixture: 8925-3
  • Bearing/Gear: 1130
  • Rings, Support: 10378

Important Warnings

Owners and technicians should be aware of several critical warnings and notes detailed in the TSB:

• Transmission Fluid Compatibility: "A unique transmission fluid has been developed for this transmission. This fluid is NOT compatible with ATF+4 or any other current FCA US LLC transmission fluid. For specifics about this unique fluid see FLUIDS, LUBRICANTS AND GENUINE PARTS."
• Electrostatic Discharge (ESD) Sensitivity: "The Transmission Control Module (TCM), or Transmission Control Module Assembly (TCMA) is extremely sensitive to Electrostatic Discharge (ESD). Always use a ground strap and follow the ESD guidelines in Electrostatic Discharge Sensitive Devices. Failure to follow these instructions may result in damage to the TCM/TCMA."
• TCM Adaptation Procedure: "If the transmission is being reconditioned (clutch/seal replacement) or replaced, it is necessary to perform the TCM Adaptation Procedure. Refer to the detailed service procedures available in DealerCONNECT/Service Library under: Service Info>08 - Electrical/8E - Electronic Control Modules/Module, Transmission Control/ Module Programming."
• Normal Debris: "It is normal for the transmission to have fine debris present in the oil pan and stuck to the magnets. Burnt oil and debris do not warrant a transmission replacement for D piston seal failure."
• Transmission Positioning: "The transmission must be in a vertical position before the main stack is removed, so damage to the drums does not occur." This note is repeated for reassembly as well.
• Seal Installation: "The seal must be installed flush with the case. Driving the seal deeper could damage the seal causing a leak."

Owner Action

If your 2021-2023 Jeep Wrangler is displaying the Malfunction Indicator Lamp (MIL) and you suspect a transmission issue, particularly if you've experienced symptoms related to incorrect gear shifting, it is recommended to contact your authorized Stellantis dealer. Provide them with the symptoms you've observed and mention the potential relevance of TSB 21-039-24 REV. F. The repair, including the replacement of the D clutch, is reimbursable within the provisions of your vehicle's warranty.

Policy

This repair is reimbursable within the provisions of the warranty.

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Source: NHTSA ID: 11009027, TSB: 21-039-24 REV. F