2020-2023 Stellantis Transmission D Clutch Repair TSB

Owners of various 2020-2023 Stellantis vehicles equipped with the Eight-Speed Auto 850RE Transmission may experience a Malfunction Indicator Lamp (MIL) illumination accompanied by specific Diagnostic Trouble Codes (DTCs). This condition points to an issue with the transmission's D clutch. Technical Service Bulletin (TSB) 21-039-24 REV. D outlines the diagnostic steps and the repair procedure to address this problem.

This bulletin, TSB 21-039-24 REV. D, supersedes TSB 21-039-24 REV. C, which was issued on September 06, 2024. The current revision includes updated repair procedures to ensure a complete and effective fix for the affected vehicles.

Symptoms

If your 2020-2023 Stellantis vehicle is affected, you will typically observe the Malfunction Indicator Lamp (MIL) illuminated on your dashboard. This warning light indicates a detected issue within the vehicle's powertrain system. In conjunction with the MIL, specific Diagnostic Trouble Codes (DTCs) will be stored in the vehicle's computer system, pinpointing the nature of the transmission fault.

Fault Codes / DTCs

The presence of one or more of the following Diagnostic Trouble Codes (DTCs) confirms the D clutch issue addressed by this TSB:

Code	Description
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

These codes specifically indicate problems with the gear ratios and the D clutch within the Eight-Speed Auto 850RE Transmission, which is the focus of this Stellantis transmission D clutch repair.

Diagnosis / Trigger Conditions

Diagnosis for this issue is straightforward: if a customer reports a lit Malfunction Indicator Lamp (MIL) and the vehicle's diagnostic system logs any of the DTCs listed above (P0733-00, P1DA8-00, or P1D92-00), the vehicle qualifies for the repair procedure outlined in TSB 21-039-24 REV. D. If these DTCs are not present, this bulletin does not apply to the vehicle's condition.

Important Warnings for Owners

Owners and technicians should be aware of several critical advisories related to this repair:

• Normal Transmission Debris: It is normal for the transmission oil pan to contain fine debris and for magnets to have particles stuck to them. The presence of burnt oil and such debris does not automatically mean a transmission replacement is needed for D piston seal failure. This information helps prevent unnecessary repairs.
• Electrostatic Discharge (ESD) Sensitivity: The Transmission Control Module (TCM) or Transmission Control Module Assembly (TCMA) is highly sensitive to electrostatic discharge. Technicians must use a ground strap and follow ESD guidelines to prevent damage to these critical components during the repair process.
• TCM Adaptation Procedure: If the transmission undergoes reconditioning, such as clutch or seal replacement, or is entirely replaced, a TCM Adaptation Procedure is mandatory. This procedure ensures the transmission control module correctly adapts to the new components.
• Clutch Pack Identification: All clutch pack assemblies should be tagged upon removal to ensure correct reassembly identification.
• Transmission Positioning: The transmission must be positioned vertically before the main stack is removed or installed. Failure to do so can cause damage to the internal drums.
• Transmission Fluid Compatibility: A unique transmission fluid is specified for this transmission. This fluid is NOT compatible with ATF+4 or any other current FCA US LLC transmission fluid. Using incorrect fluid can lead to severe transmission damage. Always refer to the FLUIDS, LUBRICANTS AND GENUINE PARTS information for specifics.
• Manual Park Release Lever: The manual park release lever can be temporarily reversed to reduce tension and simplify the installation of the valve body assembly.
• Shift Fork Alignment: During reassembly, ensure the shift fork lines up properly.
• Guide Pin Removal: After several bolts are hand-tightened during valve body installation, the guide pins must be removed.
• Seal Installation: Any seals must be installed flush with the case. Driving a seal deeper than flush can cause damage and lead to leaks.
• Output Speed Sensor Alignment: Special care must be taken to correctly align the Output Speed Sensor (OSS) guide pin during installation to prevent damage to the sensor.

Repair Procedure Summary

The repair for the Stellantis transmission D clutch issue involves a comprehensive procedure focused on replacing the D clutch within the Eight-Speed Auto 850RE Transmission. The process is intricate and requires specialized tools and expertise. Here's a summary of the key steps:

1. Initial Disassembly: The technician begins by removing external components, including the torque converter, and, if applicable, the transmission housing extension (for 4WD vehicles). The output shaft seal, output shaft snap ring, and output shaft flange (for 2WD vehicles) are then removed. The transmission oil pan is drained and removed, followed by the Hydraulic Impulse Oil Storage (H.I.S.) connector (if equipped) and the entire valve body assembly. The Output Speed Sensor and electrical harness insulator are also carefully detached.
2. Internal Component Access: Further disassembly involves removing the fluid port, fluid transfer tube, and the input shaft O-ring. The oil pump housing is then carefully pried away and removed from the transmission case.
3. Clutch and Planetary Gear Removal: The B clutch spring damper and the park pawl lock rod guide plate are removed. The input/output shaft and P4 annulus drum assembly are extracted and positioned on a specialized press fixture. The B clutch pack, P1 annulus/B clutch hub assembly, thrust bearing, holding plate, and P1 planetary carrier are then systematically removed. This provides access to the input shaft with the P2 planetary carrier, its thrust bearing and washer, and the P2 annulus/P3 sun gear. Finally, the D clutch drum, the source of the issue, is removed.
4. D Clutch Replacement: The core of the repair involves replacing the D clutch components using the appropriate D Clutch Repair Kit. This step is critical for resolving the incorrect gear ratio faults.
5. Reassembly: The transmission is reassembled by reversing the disassembly steps. This includes installing the new D clutch drum, the P2 annulus/P3 sun gear, thrust bearings, the P1 planetary carrier, and the P1 annulus/B clutch hub assembly. The B clutch pack is reinstalled, followed by the input/output shaft and P4 annulus drum assembly. The park pawl lock rod guide plate, oil pump housing (with a new input shaft O-ring), and the valve body assembly are reinstalled, ensuring proper alignment of the shift fork. The Output Speed Sensor and electrical harness insulator are carefully positioned and secured. Finally, the H.I.S. (if equipped), transmission oil pan, output shaft seals, and torque converter are reinstalled.
6. Post-Assembly Procedures: After the physical repair, the transmission is pre-filled with the specified unique transmission fluid before being reinstalled in the vehicle. The final steps involve performing a Transmission Control Module (TCM) Adaptation Procedure and a Quick Learn Procedure using the wiTECH diagnostic tool to ensure the transmission operates correctly and to clear any remaining DTCs.

Required Tools or Parts

Performing this Stellantis transmission D clutch repair requires specific parts and specialized tools to ensure accuracy and proper function. The following are essential:

D Clutch Repair Kits

• 68676890AB: D Clutch Repair Kit (4x4 JL, JT, WD, WK)
• 68676891AB: D Clutch Repair Kit (4x4 WL)
• 68676887AB: D Clutch Repair Kit (4x4 DS, DT, DX, WS)
• 68239499AD: D Clutch Repair Kit (AWD LA, LD, LX)
• 68676892AB: D Clutch Repair Kit (RWD LA, LD, LX)
• 68676894AB: D Clutch Repair Kit (RWD WD, WK)
• 68676893AB: D Clutch Repair Kit (RWD DS, DT, DX, WS)

Other Parts

• 68218925AB: Automatic Transmission Fluid (unique formulation, not compatible with ATF+4)

Special Tools

• 10377: Guide Sleeve
• 8925-3: Press Fixture
• 1130: Bearing/Gear
• 10378: Rings, Support

Owner Action

If your 2020-2023 Stellantis vehicle is exhibiting a Malfunction Indicator Lamp (MIL) and you suspect a transmission issue, particularly with the D clutch, it is recommended to schedule an appointment with an authorized Stellantis dealership. Provide them with the symptoms you're experiencing and mention the potential relevance of TSB 21-039-24 REV. D. The dealership technicians have the necessary diagnostic tools and training to confirm the presence of the specific DTCs (P0733-00, P1DA8-00, P1D92-00) and perform the required D clutch replacement. This repair is typically covered under the vehicle's warranty, provided the conditions of the TSB are met.

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Source: NHTSA ID: 11008200