P0733 on 2015-2022 Dodge Challenger: Gear 3 Incorrect Ratio Causes and Fixes

What's Unique About the 2015-2022 Dodge CHALLENGER

The Dodge Challenger in this year range, often equipped with the ZF 8-speed automatic transmission (like the 8HP70), has a well-documented history with this specific code. The manufacturer, Stellantis (formerly FCA), has released several Technical Service Bulletins (TSBs) that directly address P0733. [TSB #21-009-25 REV. C] These bulletins point to a specific internal component, the 'D' clutch, as the primary failure point, for which a specific repair kit is available. [TSB #9100390 Rev 1] This is different from many other vehicles where P0733 might be caused by a wider variety of issues like old fluid or bad solenoids. The TSBs confirm this is a known pattern failure across a wide range of Stellantis products using the same family of transmissions. [TSB #S2621000003 REV.A]

Diagnostic Flowchart

Tap your situation to follow the diagnostic path that matches what you're seeing on this vehicle.

Symptoms You May Notice

• Check Engine Light is on.
• Transmission slipping, flaring, or harsh shifting, especially during the 2-3 shift.
🎬 Watch: Understanding the causes and fixes for the P0733 code.
• Jerky or delayed shifting.
• Vehicle gets stuck in a single gear (limp mode), often 3rd gear.
• Delayed or poor acceleration.
• In some cases, the vehicle may not move in reverse, as the 'D' clutch is also involved in reverse gear.
• Abnormal noises or vibrations from the transmission area.

Most Likely Causes

1. Internal 'D' Clutch Failure 🔴 High Probability This is a known issue acknowledged by the manufacturer through multiple Technical Service Bulletins (TSBs) like #21-009-25 REV. C. [TSB #21-009-25 REV. C] The bulletins specifically call out the 'D' clutch as the failure point for P0733. The failure often involves the seals or friction materials within the clutch pack wearing out prematurely. The 'D' clutch is used in gears 4 through 8 and reverse, but the 2-3 shift often makes the slippage most apparent.
   How to confirm: A professional technician will confirm this after ruling out fluid issues and checking for related TSBs. Diagnosis involves a road test to confirm the slip in 3rd gear and analyzing transmission data with a high-level scan tool to monitor clutch operation and slip speeds. The presence of codes P1DA8-00 or P1D92-00 alongside P0733 strongly points to this failure, as they are listed together in the TSB. [TSB #21-009-25 REV. C]
   Typical fix: Replace the 'D' clutch pack using the manufacturer-specified repair kit (Part No. 68676892AB). TSB #9100390 Rev 1 explicitly states that a complete transmission replacement is NOT required for this issue. The repair involves removing the transmission, disassembling the front section to access the clutch, 🎬 Watch: How the new D-clutch overhaul kits are used. replacing the clutch pack and seals, and reassembling.
   Est. part cost: $250-$450 for the OEM repair kit.
2. Low or Dirty Transmission Fluid ⚪ Low Probability → Shop Transmission Assembly While possible, this is an unlikely root cause for P0733 on this platform given the known clutch issue. However, any transmission can suffer from low or degraded fluid. The ZF 8-speed transmission has a specific and complex procedure for checking the fluid level at a certain temperature, which can lead to incorrect levels if not done properly. Contaminated fluid can also cause solenoids to stick or passages to clog.
   How to confirm: Check the transmission fluid level and condition. This must be done with the vehicle level and the transmission fluid at a specific temperature (typically 30-50°C), with the engine running. Fluid that is dark, burnt-smelling, or low indicates a problem. However, on these vehicles, contaminated fluid is often a *symptom* of the clutch failure, not the cause.
   Typical fix: Perform a transmission fluid and filter service using the correct ZF Lifeguard 8/9 or Mopar 8&9 Speed ATF. If the fluid is very low, the source of the leak must be found and repaired. This is often attempted as a first step but rarely resolves the P0733 code permanently if the D-clutch is already damaged.
   Est. part cost: $200-$400 for OEM fluid and a new pan/filter assembly.
3. Faulty Valve Body or Shift Solenoid ⚪ Low Probability → Shop Transmission Valve Body Solenoids or the valve body (mechatronics unit) can fail on any automatic transmission, causing hydraulic pressure issues that lead to slipping. While less common than the D-clutch failure on this platform for this specific code, it's a possibility, especially if shifting issues are erratic across multiple gears and not just isolated to the 2-3 shift.
   How to confirm: A technician can command the solenoids using a diagnostic scan tool and monitor pressure readings. A failure to respond or incorrect pressure would point to a solenoid or valve body issue. This is an advanced diagnostic step performed after fluid level/condition is verified.
   Typical fix: Replace the faulty shift solenoid or the entire mechatronic unit (valve body and TCM assembly). This is a costly repair and should only be performed after definitive diagnosis.
   Est. part cost: $500-$1500 depending on whether a single solenoid or the full mechatronic unit is replaced.

Diagnosis Steps

1. Verify the code with a quality OBD-II scanner.
2. Check for any accompanying codes, especially P1DA8 and P1D92, as they strongly point to the known TSB issue. [TSB #21-009-25 REV. C]
3. Search for applicable TSBs using the vehicle's VIN. For this vehicle and code, TSBs #21-009-25 and #9100390 are highly relevant.
4. Check the transmission fluid level and condition following the exact manufacturer procedure (vehicle level, specific fluid temperature of 30-50°C, engine running).
5. If fluid is correct, perform a road test to confirm the slip or harsh shift into 3rd gear. Note if symptoms change as the transmission warms up.
6. Using an advanced scan tool, monitor transmission PIDs for input speed, output speed, and commanded gear to confirm the slip is occurring in 3rd.
7. If symptoms and codes align with the TSBs, the next step is to proceed with the 'D' clutch replacement procedure outlined in the service bulletin. [TSB #21-009-25 REV. C]
8. If symptoms are atypical (e.g., erratic shifting in all gears), further diagnosis of the valve body, solenoids, and wiring may be needed.

Parts You'll Likely Need

• D Clutch Repair Kit (OEM #68676892AB) — This is the specific kit identified by Dodge in TSBs to fix the root cause of P0733 on these transmissions. It contains the necessary clutches, steels, and seals for the D-clutch assembly.
  Trusted brands: Mopar
  OEM price range: $250-$450
  Aftermarket price range: N/A
• Automatic Transmission Fluid (Mopar ZF 8&9 Speed or equivalent) (OEM #68218925AB) — The transmission must be refilled with the correct fluid after the repair. Using a non-approved fluid can cause shifting problems and damage. ZF Lifeguard 8 or 9 are also approved.
  Trusted brands: Mopar, ZF
  OEM price range: $25-$40 per liter
  Aftermarket price range: $20-$30 per liter
• Transmission Pan with Integrated Filter (OEM #68225344AA) — The plastic pan must be removed for the repair and contains the non-serviceable filter. It is required practice to replace it during this service. The kit includes the pan, gasket, and new bolts.
  Trusted brands: Mopar, ZF
  OEM price range: $150-$250
  Aftermarket price range: $100-$200

Related Codes That Often Appear With This One

• P1DA8-00 — This code for 'Incorrect Gear Ratio Clutch A B or D Defective' is listed in the same TSBs as P0733 and points to the same internal clutch pack failure. [TSB #21-009-25 REV. C]
• P1D92-00 — This code for 'Incorrect Gear Ratio - Clutch 4 Defective' is also listed alongside P0733 in manufacturer bulletins, indicating a related internal fault within the D-clutch assembly. [TSB #21-009-25 REV. C]

Technical Service Bulletins (TSBs) & Recalls

• 21-009-25 REV. C: Defines P0733-00 as 'Gear 3 Shift Incorrect Ratio' and links it to a required D-clutch repair. It lists affected vehicles and other related DTCs.
• 9100390 Rev 1: Mentions a 'D Clutch Repair Kit' for P0733 and explicitly states that a complete transmission replacement is NOT required for this specific issue.
• S2621000003 REV.A: A general TSB that lists P0733 as a potential code for the 8HP series transmissions used in these vehicles.
• 21-039-24 REV. D: Provides detailed repair instructions and part numbers for the D clutch replacement, superseding earlier versions and expanding the vehicle list.

Platform-Specific Known Issues

• Multiple TSBs (e.g., 21-009-25 REV. C, 9100390 Rev 1) have been issued by the manufacturer specifically for P0733 and related codes, pointing to a defect in the 'D' clutch pack.
• The repair requires internal transmission work, but Dodge explicitly states that a full transmission replacement is not necessary, providing a specific clutch repair kit instead. [TSB #9100390 Rev 1]
• The issue is not unique to the Challenger; it affects a wide range of Stellantis vehicles using the same ZF 8-speed transmission family, including Ram trucks, Jeep Grand Cherokees, and Dodge Chargers.

Mechanic-Grade Diagnostic Values

• Shift Solenoid Resistance (Variable Force Solenoids) — expected: Approximately 5.0 - 5.5 Ohms at 20°C (68°F).. Failure: A reading significantly outside this range indicates a faulty solenoid coil.
• Solenoid Vacuum Test — expected: A known-good solenoid should hold a steady vacuum of over 20 in-Hg when tested with a manifold kit.. Failure: A reading below 20 in-Hg or a failure to hold vacuum indicates internal leaks in the solenoid.

Scan Tool Commands That Help

• wiTECH, Autel, or other professional-grade scan tool: Reset Adaptive Values / Transmission Quicklearn — This function is critical after replacing internal transmission components like the D-clutch kit. It erases the TCM's old learned values for clutch engagement pressures and timing. After the reset, a specific drive cycle is required to allow the TCM to learn the characteristics of the new parts for smooth shifting.
• wiTECH: Reprogram Transmission Control Module (TCM) — Used to update the TCM with the latest manufacturer software, which can address shift quality enhancements or logic changes. This is often a preliminary step before mechanical repairs are authorized.

Wiring & Ground Locations

• F29 and F37 — Located in the underhood fuse box (passenger side of the engine bay).. These are primary power supply fuses for the Transmission Control Module (TCM). A loss of power here would cause a loss of communication and multiple codes, but they should be checked as a preliminary step.
• F26 — Located in the rear fuse box in the trunk, near the battery.. This is another potential fuse for the TCM, depending on the vehicle's specific configuration. Some vehicles may not have this fuse populated.

OEM Part Supersession History

• 68676892AA → 68676892AB — This is a routine part number revision by the manufacturer, likely for minor improvements or supplier changes.
  Heads up: The new part number (68676892AB) is the correct and current replacement for the old one.

Model Year Variations Within This Range

• 2015-2022: Within this range, Challengers may be equipped with either the first-generation ZF 8HP70 or the second-generation 8HP75. The 8HP75 features improvements like an optimized oil pump. However, the TSBs related to P0733 and the D-clutch failure apply broadly across these model years, indicating the fundamental design vulnerability is present in both transmission generations used in this platform.