P0876 on 2024 Ram 2500: Transmission Pressure Sensor 'D' Circuit Causes and Fixes

What's Unique About the 2024-2024 Ram 2500

For the 2024 Ram 2500 equipped with the 6.7L Cummins engine and 68RFE transmission, P0876 is not just a simple sensor code. Multiple Technical Service Bulletins (TSBs), including 21-012-25 REV. C and others, link this code to a significant internal mechanical failure: a cracking rear selective thrust bearing. This issue is specific to trucks built between June 14, 2024, and September 04, 2024. The failure causes a catastrophic loss of hydraulic pressure, triggering P0876 along with other codes like P0868 (Transmission Fluid Pressure Low) and P0944 (Loss Of Hydraulic Pump Prime). The manufacturer's recommended repair in this scenario is a complete transmission replacement, highlighting the severity of the problem on this specific platform.

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 illumination
• Vehicle enters 'limp home mode'
• Hard, erratic, or delayed shifting
• Transmission slipping
• Inability to shift gears or getting stuck in one gear
• Loss of power when accelerating
• Thump or clunk noise during shifting

Most Likely Causes

1. Cracked Rear Selective Thrust Bearing (6.7L Cummins with 68RFE) 🔴 High Probability A known manufacturing defect documented in TSBs 21-012-25 and 21-054-24 for vehicles built between June 14, 2024, and September 04, 2024. This internal failure leads to a system-wide loss of hydraulic pressure.
   How to confirm: Diagnosis by a qualified technician following the steps in the relevant TSB. This involves verifying the VIN and build date fall within the affected range and observing the cluster of related trouble codes (P0868, P0944, P0871).
   Typical fix: Complete transmission replacement, as specified by the manufacturer bulletin. Some later bulletins discuss an internal repair of the thrust plate, but replacement is the most cited fix for symptomatic vehicles.
   Est. part cost: $6000-$9000+
2. Faulty Transmission Solenoid/Valve Body Assembly 🟡 Medium Probability The pressure switches are integrated into the solenoid pack, which is a known failure point on 68RFE transmissions. The valve body itself can also develop cross-leaks, leading to pressure control issues.
   How to confirm: Requires advanced diagnostics with a scan tool to monitor sensor data and command shifts. May require removing the transmission pan for inspection of the valve body and solenoid pack. This is the likely cause if the vehicle is outside the TSB build dates.
   Typical fix: Replacement of the solenoid pack or the entire valve body assembly. 🎬 Watch: Step-by-step guide to installing a new 68RFE valve body. Aftermarket billet valve bodies are a popular upgrade to prevent future issues.
   Est. part cost: $350-$1200
3. Low or Overfilled Transmission Fluid Level 🟡 Medium Probability Incorrect fluid level is a common cause for pressure-related codes in any automatic transmission. Both low and high fluid levels can cause aeration and pressure deviations, triggering P0876 or P0868.
   How to confirm: Check the transmission fluid level and condition according to the manufacturer's procedure (vehicle at operating temperature, running in neutral on a level surface). The fluid should be at the correct level, not smell burnt, and be free of bubbles.
   Typical fix: Adjust fluid to the correct level using Mopar ATF+4 fluid and inspect for leaks or signs of overfilling.
   Est. part cost: $20-$80

Rare But Worth Checking

• Wiring or Connector Issue: Damage to the transmission wiring harness or corrosion in the main connector can cause erratic signals from the pressure sensor. A visual inspection is always a worthwhile diagnostic step.
• Faulty Transmission Control Module (TCM): While rare, the TCM itself can fail, causing false codes. This should only be considered after all other possibilities, especially the TSB, valve body, and fluid level, have been exhaustively ruled out.

Diagnosis Steps

1. Check the vehicle's build date and VIN to see if it falls within the range specified by TSBs 21-012-25 or 21-054-24 (June 14, 2024 - September 04, 2024).
2. Scan the TCM for all stored trouble codes. Note if P0868, P0944, or P0871 are present alongside P0876, as this strongly indicates the TSB issue.
3. If the vehicle falls under the TSB, follow the manufacturer's recommended repair, which is likely a transmission replacement.
4. If the vehicle is outside the TSB scope, begin with standard diagnostics: check the transmission fluid level and condition. Ensure the correct procedure is followed (hot, level ground, in neutral).
5. Inspect the main transmission wiring harness connector for corrosion or damage.
6. Use an advanced scan tool to monitor live data from all transmission fluid pressure sensors while the engine is running and during shifts.
🎬 Watch: Professional webinar on advanced 68RFE transmission diagnostics and data monitoring.
7. If fluid and wiring are good, the next logical step is to drop the transmission pan to inspect the internal components, starting with the valve body and solenoid pack.

Parts You'll Likely Need

• Complete Transmission Assembly — For vehicles affected by TSB 21-012-25, this is the manufacturer-mandated fix for the underlying cracked thrust bearing issue.
  Trusted brands: Mopar (Remanufactured)
  OEM price range: $6000-$9000+
  Aftermarket price range: N/A
• Transmission Solenoid Pack / Valve Body (OEM #68456067AA (Solenoid Pack for 2019+)) — If the issue is not the TSB-related failure, a faulty solenoid pack or valve body is a common cause for pressure-related codes in the 68RFE transmission.
  Trusted brands: Mopar, Rostra, BD Diesel, RevMax
  OEM price range: $600-$900
  Aftermarket price range: $400-$1200
• Mopar ATF+4 Transmission Fluid (OEM #68218057AC (Quart), 68218058AC (Gallon)) — Required for any repair that involves opening the transmission, such as topping off fluid or replacing the valve body. Using the correct fluid is critical for 68RFE longevity.
  Trusted brands: Mopar, Valvoline ATF+4
  OEM price range: $15-$25 per quart
  Aftermarket price range: $10-$20 per quart

Related Codes That Often Appear With This One

• P0868 — Transmission Fluid Pressure Low - Often appears with P0876 as part of a systemic pressure loss, as noted in TSBs for the thrust bearing failure.
• P0944 — Loss Of Hydraulic Pump Prime - Also cited in TSBs alongside P0876, indicating a severe hydraulic circuit failure.
• P0871 — Transmission Fluid Pressure Sensor/Switch 'C' Circuit Range/Performance - Indicates another pressure circuit is also failing, pointing towards a larger issue than a single sensor, consistent with the TSB.
🎬 See how to diagnose and repair common valve body pressure issues.
• P0700 — Transmission Control System Malfunction - This is a generic code indicating the TCM has stored a fault, which in this case is P0876.

Technical Service Bulletins (TSBs) & Recalls

• M21 FSAR-TSB-4997 (NHTSA ID: 21-012-25 REV. A): Confirms the cause as a cracked rear selective thrust bearing for trucks built June-Sept 2024 and mandates transmission replacement.
• M21 FSAR-TSB-5476 (NHTSA ID: 21-012-25 REV. C): A revision of the previous bulletin, confirming the issue and repair procedure for the same set of vehicles and codes.
• J21 FSAR-RSU-4774 (NHTSA ID: 21-054-24 REV. D): A related bulletin that discusses a proactive repair for unsold vehicles, involving replacement of the thrust plate and reaction sun gear internally.

Platform-Specific Known Issues

• A series of Technical Service Bulletins (including #21-012-25 REV. C and #21-054-24 REV. D) identifies a critical issue in 2024 Ram 2500s with the 6.7L Cummins and 68RFE transmission built between June 14, 2024, and September 04, 2024. The cause of P0876 and other pressure codes is a 'Rear selective thrust bearing cracking,' with the official repair for symptomatic vehicles being a full transmission replacement.

Mechanic-Grade Diagnostic Values

• Underdrive (UD) Solenoid Resistance — expected: 1.3 Ohms. Failure: A reading significantly higher or lower than 1.3 Ohms indicates a faulty solenoid coil.
• UD Pressure Switch Sense Circuit Resistance — expected: Below 5.0 Ohms. Failure: Resistance above 5.0 Ohms indicates an open or high-resistance in the wiring between the solenoid assembly connector and the TCM/PCM.
• UD Pressure Switch Sense Circuit Short to Ground — expected: Open circuit (infinite resistance). Failure: Resistance below 5.0 ohms indicates a short to ground in the circuit.
• Pressure Switches (General) — expected: Switches close at 23 psi and open at 11 psi.. Failure: A switch that is stuck open or closed, or activates outside this pressure range, is faulty. This is monitored by the TCM by comparing switch states to the current gear.

Scan Tool Commands That Help

• wiTECH or equivalent OE-level scanner: Quick Learn Procedure — This function must be performed after replacing the transmission, valve body, or solenoid pack. It allows the TCM to learn the hydraulic characteristics (Clutch Volume Index - CVI) of the new components for proper shift timing.
• wiTECH or equivalent OE-level scanner: TCM/ECM Reset — This should be performed before the Quick Learn procedure to clear out old adaptive and learned values from the control module.
• wiTECH 2.0: Loss of Comm Test — If intermittent electrical issues are suspected, this test continuously 'pings' all modules on the network to see if any are dropping out. This can help identify a wiring harness issue or failing TCM that might not set a hard fault.

Wiring & Ground Locations

• Transmission Solenoid/TRS Assembly Connector — On the driver's side of the transmission case, a large round connector that plugs into the solenoid pack/valve body assembly.. This is the main electrical interface for all internal transmission electronics, including the Underdrive ('D') pressure switch. P0876 is specifically for the '(T29) UD Pressure Switch Sense circuit' which runs through this connector. Corrosion or pushed-out pins here are a primary diagnostic check.
• TCM C1 and C4 Connectors — The Transmission Control Module (TCM) is located at the rear of the engine compartment, near the right (passenger side) inner fender.. The sense circuit from the pressure switch terminates at the TCM. A diagnostic test involves checking resistance from the transmission connector all the way to the TCM connector to find opens or shorts in the harness.
• Transmission Control Relay — Located in the Integrated Power Distribution Module (IPDM), also known as the under-hood fuse box, typically on the driver's side fender well.. While not a direct cause of a single pressure switch code, a faulty relay can cause intermittent power loss to the entire TCM, leading to multiple erratic codes and limp mode.

Real Owner Repair Stories

• RamForum.com user (2012 Ram (unknown engine/trim)) — Vehicle went into limp mode (4th gear), initially threw a code for the solenoid pack. After replacement, it would intermittently thump, downshift to 4th, and set code P0876.
  ❌ Tried (didn't work) Replacing the transmission solenoid pack.
  ✅ What actually fixed it The user did not post a final fix, but another senior member suggested the next step was a valve body replacement due to common cross-leaks in the 68RFE, which would not be solved by a solenoid pack alone.
• DodgeForum.com user (3rd Gen Ram (2002-2008)) — Check engine light on, truck stuck in 3rd gear.
  ❌ Tried (didn't work) Initial diagnosis was unclear.
  ✅ What actually fixed it The dealer diagnosed and replaced a 'frozen' transmission solenoid. The repair involved dropping the transmission pan and valve body to access and replace the solenoid pack.

OEM Part Supersession History

• 68367309AA, 68456067AA → 68456067AB — Standard part revision by the manufacturer for improvements or manufacturing changes.
  Heads up: The solenoid pack for 2019+ models has a blue connector and is not interchangeable with earlier (typically white or gray connector) versions.

Model Year Variations Within This Range

• 2019+: Solenoid packs for 2019 and newer 68RFE transmissions use a different (blue) electrical connector than prior years and are not cross-compatible. The part number is 68456067AA, which has been superseded by 68456067AB.