P0732 on 2024 Ram 3500: Gear 2 Incorrect Ratio Causes and Fixes

What's Unique About the 2024-2024 Ram 3500

For the 2024 Ram 3500, this code is particularly serious and often points to known, significant mechanical failures rather than simple sensor issues. Depending on the transmission (either the Aisin AS69RC or the Chrysler 68RFE), the cause can be a widespread issue. For the 68RFE, TSB 21-012-25 REV. E points to a cracking rear selective thrust bearing on trucks built between June and September 2024. For the Aisin AS69RC, a known K1 clutch drum snap ring failure can cause a loss of gears 1-4. 🎬 Watch: A mechanic explains the Aisin K1 snap ring failure In both cases, the manufacturer's recommended repair is often a complete transmission replacement.

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, especially in 2nd gear
• Harsh, delayed, or failed shifts into 2nd gear
• Engine revs higher than normal before a gear engages
• Reduced acceleration or the vehicle entering 'limp mode'
• Grinding or whining noises from the transmission
• Sudden loss of gears 1-4, with only 5th and Reverse functional (Aisin K1 failure)
• Vehicle may die or stall when coming to a stop after highway driving

Most Likely Causes

1. Internal Mechanical Failure (Cracked Thrust Bearing / K1 Snap Ring) 🔴 High Probability TSB #21-012-25 REV. E specifically identifies a cracking rear selective thrust bearing as a cause for this and other codes on 2024 models with the 68RFE transmission built between June 14, 2024, and September 04, 2024. Similarly, the Aisin AS69RC transmission has a documented issue with K1 clutch snap ring failure, which has been the subject of NHTSA investigations and customer satisfaction notices for various model years.
   How to confirm: Diagnosis requires checking for specific TSBs related to the vehicle's VIN and build date. For the 68RFE, the presence of a cluster of DTCs listed in TSB 21-012-25 REV. E confirms the diagnosis. For the Aisin, a technician may need to drop the pan to inspect for debris; however, the TSB for this issue requires transmission removal to inspect the K1 and K2 clutch assemblies.
   Typical fix: For the issue described in TSB 21-012-25 REV. E, the official repair is a complete transmission replacement. For the Aisin K1 snap ring failure, the fix involves transmission removal and replacement of the K1 clutch drum snap ring and potentially the K1 and K2 clutch assemblies.
   Est. part cost: $4000-$9000
2. Low or Contaminated Transmission Fluid 🟡 Medium Probability → Shop Transmission Assembly While major mechanical failure is a high probability, low or burnt fluid is a fundamental cause of slipping and hydraulic pressure loss that must be ruled out first. Contaminated fluid can cause solenoids to stick or internal passages to clog.
   How to confirm: Check the transmission fluid level and condition according to the owner's manual. The fluid should be bright red, clear, and not smell burnt. On some forums, owners have noted that low fluid was the cause, even without visible leaks.
   Typical fix: Top off the fluid to the correct level or perform a complete fluid and filter change. Use only the OEM-specified fluid (Mopar ATF+4 for 68RFE, Mopar ASRC for Aisin).
   Est. part cost: $50-$250
3. TCM Software Issue 🟡 Medium Probability Multiple TSBs for Ram trucks indicate that software updates are a common remedy for false or intermittent incorrect gear ratio codes by addressing faulty shift logic or sensor interpretation. A software update can correct how the TCM interprets data from sensors and controls shifts.
   How to confirm: A dealership or qualified shop can check the current TCM software version against the latest available version from the manufacturer using a wiTECH scan tool.
   Typical fix: Update the Transmission Control Module (TCM) software. This is a common first step before more invasive repairs are approved.
   Est. part cost: $0-$250
4. Faulty Shift Solenoid or Valve Body ⚪ Low Probability → Shop Transmission Valve Body Debris in the fluid can cause solenoids to stick or valve bodies to malfunction, leading to pressure loss in the 2nd gear hydraulic circuit. The 68RFE in particular is known to have issues with the solenoid pack.
   How to confirm: A technician can test solenoid resistance and function with a scan tool. A diagnostic procedure for the 68RFE involves checking CVI (Clutch Volume Index) values 🎬 See how to diagnose common 68RFE transmission problems for the 2C clutch; if the value is out of the normal range (25-85) or continues to increase over time, it indicates a leak in the 2C clutch circuit.
   Typical fix: Replace the specific shift solenoid for 2nd gear or the entire solenoid pack/valve body assembly. A Mopar OEM solenoid pack for the 68RFE is available.
   Est. part cost: $250-$700

Rare But Worth Checking

• Faulty Input/Output Speed Sensor: While possible, a bad speed sensor will usually set its own specific trouble code (e.g., P0716, P0722) in addition to the gear ratio code. TSB 21-012-25 REV. E lists P0716 as a related code for the thrust bearing failure.
• Wiring Harness Issues: Corroded pins or damaged wires between the TCM and the transmission can distort signals, but this is less common than internal mechanical or hydraulic issues.

Diagnosis Steps

1. Check for any active Technical Service Bulletins (TSBs) for your vehicle's VIN. TSB 21-012-25 REV. E is critical for 2024 models with the 68RFE transmission built between June and September 2024.
2. With a capable scan tool, check for all other transmission and engine codes. The presence of other gear ratio codes or pressure codes is highly significant.
3. Check the transmission fluid level and condition. The fluid must be at the correct level, at operating temperature, and not appear dark, burnt, or contain metal particles.
4. If the fluid is clean and the level is correct, check for available TCM software updates with a dealership or qualified shop.
5. If software is up-to-date, the next step is typically to drop the transmission pan 🎬 Watch: 68RFE teardown to see internal components and damage and inspect for metal debris on the magnet and in the pan, which would confirm internal mechanical failure.
6. For 68RFE transmissions, a technician may check the Clutch Volume Index (CVI) values with a scan tool to identify internal clutch circuit leaks.
7. If a known TSB applies (like 21-012-25 REV. E), the diagnosis is confirmed by the VIN and DTCs, and the prescribed repair (transmission replacement) should be followed.

Parts You'll Likely Need

• Complete Transmission Assembly (68RFE or Aisin) — TSB 21-012-25 REV. E explicitly calls for the replacement of the entire 68RFE transmission as the official repair for a known defect causing this code on some 2024 models. For severe Aisin failures, replacement may also be more cost-effective than a rebuild.
  Trusted brands: Mopar
  OEM price range: $6000-$9000
  Aftermarket price range: $4000-$7000
• Transmission Fluid and Filter Kit (OEM #5013470AE (68RFE Sump Filter)) — This is the first step in diagnosis and a required part of any major transmission service. Using the correct fluid is critical. The Mopar 68RFE sump filter part number is 5013470AE.
  Trusted brands: Mopar
  OEM price range: $150-$250
  Aftermarket price range: $80-$150
• K1 Clutch Drum Snap Ring / Assembly (Aisin AS69RC) — For Aisin transmissions, this is the specific point of failure. The repair involves replacing the snap ring and inspecting/replacing the K1 and K2 clutch assemblies.
  Trusted brands: Mopar
  OEM price range: $200-$500

Related Codes That Often Appear With This One

• P0731, P0733, P0734, P0735, P0729 — These are incorrect gear ratio codes for other gears. Seeing them together strongly suggests a systemic problem like the one described in TSB 21-012-25 REV. E for the 68RFE.
• P0868 — This code means 'Transmission Fluid Pressure Low'. It directly supports the theory of an internal hydraulic leak or pump issue causing the gear slip and is listed as a related code in TSB 21-012-25 REV. E.
• P0716 — This code for 'Input Speed Sensor 1 Circuit Performance' is often listed alongside the incorrect ratio codes in manufacturer TSBs, pointing to a complex control system fault, such as the thrust bearing failure.
• P0944 — This code for 'Loss of Hydraulic Pump Prime' is also linked in TSBs to the same cracking thrust bearing issue, often requiring transmission replacement.

Technical Service Bulletins (TSBs) & Recalls

• 21-012-25 REV. E: Addresses multiple incorrect gear ratio DTCs, including P0732, caused by a cracking rear selective thrust bearing on some 2024 Ram 2500 and 3500 models with the 68RFE transmission. The specified repair is transmission replacement.
• 21-002-23: (Referenced in news articles) Pertains to the Aisin AS69RC/AS66RC K1 clutch drum snap ring failure on 2019-2023 models, requiring transmission disassembly to replace the ring and inspect related clutch components.

Platform-Specific Known Issues

• TSB #21-012-25 REV. E: Cracking Rear Selective Thrust Bearing (68RFE): Identifies a cracking rear selective thrust bearing as the cause for P0732 and a host of other gear ratio and pressure codes on 2024 Ram HD trucks with the 68RFE transmission. This TSB applies specifically to vehicles built between June 14, 2024, and September 04, 2024. The prescribed fix is a complete transmission replacement, as the failure contaminates the entire unit with debris.

Mechanic-Grade Diagnostic Values

• 68RFE Clutch Volume Index (CVI) for 2C Clutch — expected: 25-85. Failure: A value outside this range, or one that consistently increases over time, indicates a leak in the 2C clutch hydraulic circuit, which is used for 2nd gear.
• Aisin AS69RC PWM Solenoid Resistance — expected: 4-6 Ohms. Failure: A resistance reading outside of this range indicates a faulty solenoid coil. This applies to the small yellow connector and larger black connector solenoids.
• Aisin AS69RC On/Off Solenoid Resistance — expected: 11-21 Ohms. Failure: A resistance reading outside of this range indicates a faulty solenoid coil. This applies to the green connector solenoid.
• 68RFE Input/Output Speed Sensor Resistance — expected: Approximately 535 Ohms at room temperature. Failure: A significantly different reading or an open/short circuit indicates a failed sensor.

Scan Tool Commands That Help

• wiTECH: Quick Learn — This must be performed after replacing the transmission, valve body, or TCM, or after clearing adaptation memory. It resets and begins the re-learning process for the transmission's clutch application timing. It is often a required first step for any shift quality complaint.
• wiTECH: Drive Learn Procedure — After performing a 'Quick Learn', the vehicle must be driven in a specific manner (e.g., moderate acceleration through gears, kickdown shifts) to allow the TCM to update the Clutch Volume Index (CVI) values for each clutch pack under real-world conditions.
• wiTECH: Flash/Reprogram TCM — Used to update the transmission control module's software to the latest version. This can resolve incorrect gear ratio codes that are caused by software logic errors rather than mechanical faults.

Wiring & Ground Locations

• Transmission Harness Splices (e.g., S109) — Various splices are located within the main transmission harness itself or at the rear of the engine compartment.. Corrosion or damage at a splice within the harness can disrupt communication between the TCM and transmission components like speed sensors or solenoids, leading to ratio codes.
• Main Transmission Harness Connector — Connects the main vehicle harness to the transmission; location varies depending on 68RFE or Aisin model.. This is the primary electrical interface. Water intrusion, corrosion on pins, or a loose connection here can cause a multitude of transmission codes, including P0732.

Real Owner Repair Stories

• Reddit user in r/transmissionbuilding (2024 Ram 3500 4x4 Diesel with 68RFE) — P0734 (4th gear incorrect ratio) and P0933 (pressure control solenoid) after installing a deep transmission pan.
  ❌ Tried (didn't work) Transmission service and deep pan installation preceded the fault.
  ✅ What actually fixed it The community diagnosis pointed directly to a slipping overdrive clutch. The recommended next step was to check the Clutch Volume Index (CVI) values with a scan tool to confirm the internal clutch failure before proceeding with a teardown.
• Dodge Diesel Forum user (2013 Ram with Aisin AS69RC) — P0974 (Shift Solenoid 'A' Control Circuit High)
  ❌ Tried (didn't work) Pulled transmission pan., Removed and tested resistance on all solenoids (all tested okay)., Traced internal transmission wiring to check for shorts (none found).
  ✅ What actually fixed it The user concluded the problem was most likely the Transmission Control Module (TCM) itself, as all accessible components and wiring tested good. This highlights a scenario where individual parts are not at fault, pointing to a controller failure. The user also noted the dealer does not sell individual solenoids, only a complete valve body assembly for a high cost.

OEM Part Supersession History

• Varies (White Connector) → 68456067AA (Blue Connector) — Updated design for 2019+ model year 68RFE transmissions.
  Heads up: The 68RFE solenoid packs use different colored connectors (e.g., white, grey, blue) depending on the model year. While some earlier packs may be physically interchangeable, using the wrong one can cause performance issues. For a 2024 model, the correct Mopar part number must be used, which is likely the blue connector version (68456067AA or its successor).

Model Year Variations Within This Range

• 2024 (Specifically June 14, 2024 - Sept 04, 2024 build dates): Models with the 68RFE transmission built in this window are subject to TSB 21-012-25 REV. E for a cracking rear selective thrust bearing, which is a primary cause of P0732 and requires transmission replacement.