P0841 on 2024 Ram 3500 6.7L Cummins: Causes for Transmission Pressure Sensor Faults

What's Unique About the 2024-2024 Ram 3500

For the 2024 Ram 3500, the diagnosis of P0841 is critically dependent on the vehicle's build date and which 6-speed automatic it has. The 6.7L Cummins can be paired with either the Chrysler 68RFE or the Aisin AS69RC transmission. A crucial Technical Service Bulletin (TSB 21-012-25 REV. E) applies specifically to trucks with the 68RFE built between June 14, 2024, and September 04, 2024. For this specific group of vehicles, P0841 is a primary indicator of a cracking rear selective thrust bearing, a catastrophic internal failure where the only factory-authorized repair is a complete transmission replacement. For trucks outside this build window or those with the Aisin transmission, the causes are more conventional, such as fluid, sensor, or wiring issues.

Symptoms You May Notice

• Check Engine Light (Malfunction Indicator Lamp) is on
• Harsh, erratic, or delayed shifting
• Transmission stuck in one gear (limp mode)
• Vehicle may stall when put into gear
• Transmission warning light may be illuminated
• Increased fuel consumption

Most Likely Causes

1. Internal Transmission Failure (Cracked Thrust Bearing) 🔴 High Probability Applies specifically to 2024 Ram 2500/3500 with the 68RFE transmission built between June 14, 2024, and September 04, 2024, as identified in TSB 21-012-25 REV. E.
   How to confirm: A dealer must verify the vehicle's build date against the TSB. The presence of P0841 along with other codes like P0868 (Transmission Fluid Pressure Low), P0944 (Loss Of Hydraulic Pump Prime), or various incorrect gear ratio codes (P073x) strongly indicates this failure.
   Typical fix: Complete transmission replacement is the only repair authorized by the manufacturer for this specific issue per the TSB.
   Est. part cost: $6000-$8000+
2. Low, Dirty, or Incorrect Transmission Fluid 🔴 High Probability This is the most common cause for vehicles outside the TSB window. The 68RFE is sensitive to fluid level and condition for proper hydraulic pressure. Using the wrong fluid can also cause issues.
   How to confirm: Check the transmission fluid level and condition. The fluid should be at the correct level, red in color, and not smell burnt. Note that these trucks do not have a user-serviceable dipstick, requiring a specific shop procedure to check the level. The correct fluid for the 68RFE is Mopar ATF+4.
   Typical fix: Perform a transmission fluid and filter change using the correct fluid (Mopar ATF+4 for the 68RFE).
   Est. part cost: $100-$250
3. Faulty Transmission Fluid Pressure Sensor / Solenoid Pack 🟡 Medium Probability The pressure sensor (switch) is integrated into the Transmission Solenoid/TRS Assembly on the valve body. This electronic component is a known failure point on 68RFE transmissions and can fail over time. For 2019+ models, this is often a blue-connector solenoid pack.
   How to confirm: A technician can use a high-end scan tool to monitor the L/R Pressure Switch data in real-time while driving or using a transmission simulator. If the switch state doesn't change correctly with gear changes and wiring is good, the sensor is likely faulty. On Reddit, one owner noted replacing the sensor and valve body did not fix the issue, highlighting the need for proper diagnosis.
   Typical fix: Replace the entire Transmission Solenoid/TRS Assembly, which is located inside the transmission oil pan on the valve body. For 2019+ models, the new solenoid pack may need to be coded to the vehicle's ECM.
   Est. part cost: $300-$500
4. Wiring Harness or Connector Issue ⚪ Low Probability The main transmission harness connector can corrode, and the harness itself can chafe against the frame or other components, leading to an open or short circuit. A user on a Cummins forum mentioned the area near the driver's side mudflap as a common chafe point.
   How to confirm: Visually inspect the wiring harness running to the transmission for any signs of damage, rubbing, or corrosion at the main connector. A multimeter can be used to test for continuity and shorts in the L/R pressure switch circuit. A "wiggle test" on the harness while monitoring live data can help find intermittent faults.
   Typical fix: Repair the damaged section of the wiring harness or clean/replace the affected connector.
   Est. part cost: $50-$300

Rare But Worth Checking

• Faulty Powertrain Control Module (PCM): This is extremely rare. The PCM should only be considered after all other possibilities, including fluid, sensor, wiring, and internal mechanical issues, have been definitively ruled out by a professional.
• Cracked or Blocked Valve Body: Though less common than a solenoid failure, the valve body itself can develop internal cracks, cross-leaks, or have stuck check balls, which can cause pressure regulation issues and trigger a P0841 code. Aftermarket companies like Sonnax offer upgraded valve bodies to address these weaknesses.

Diagnosis Steps

1. Check the vehicle's build date to see if it falls between June 14, 2024, and September 04, 2024. If it does, and the transmission is a 68RFE, immediately refer to TSB 21-012-25 REV. E.
2. Scan the system for all DTCs. Note if P0841 is accompanied by other codes listed in the TSB (P0868, P0944, P073x, etc.), as this strongly points to the internal failure.
3. If the vehicle is outside the TSB window, begin by checking the transmission fluid level and condition. This requires a shop procedure as there is no dipstick. Ensure Mopar ATF+4 fluid is used.
4. Inspect the main transmission wiring harness and its connector on the driver's side of the transmission for corrosion, damage, or loose connections. Pay attention to common chafe points along the frame.
5. Using a professional scan tool, monitor the L/R Pressure Switch status while commanding different gears. The switch should read 'Open' or 'Closed' according to the factory service manual's pressure switch state chart.
6. If the switch state is irrational and the wiring is confirmed to be good, the fault is likely the pressure switch itself, which is part of the solenoid pack inside the transmission.
7. If all sensor and circuit tests pass, the issue may be a more complex internal mechanical problem, such as a sticking valve in the valve body or a failing clutch pack.

Parts You'll Likely Need

• Complete Transmission Assembly — This is the required fix for vehicles falling under TSB 21-012-25 REV. E due to an internal manufacturing defect. Mopar lists new 2WD 68RFE transmissions for around $7,200 MSRP.
  Trusted brands: Mopar, Jasper, Tier One, BD Diesel
  OEM price range: $6000-$8000+
  Aftermarket price range: $4000-$7000+
• Transmission Solenoid / TRS Assembly (OEM #68353383AB) — For trucks not affected by the TSB, this part is the most likely culprit if the fluid is good. It contains the pressure sensor/switch that triggers the P0841 code. The 2019+ models use a blue connector pack.
  Trusted brands: Mopar, Sonnax, RevMax
  OEM price range: $365-$500
  Aftermarket price range: $250-$450
• Mopar ATF+4 Automatic Transmission Fluid — Required for fluid top-off or a fluid and filter service, which is the first diagnostic step for trucks outside the TSB window.
  Trusted brands: Mopar
  OEM price range: $10-$15 per quart

Related Codes That Often Appear With This One

• P0868 — Indicates 'Transmission Fluid Pressure Low'. This code is often seen with P0841, especially when the cause is low fluid or the internal failure described in TSB 21-012-25 REV. E.
• P0944 — Indicates 'Loss Of Hydraulic Pump Prime'. This points to a fundamental fluid supply issue and is another key code listed in TSB 21-012-25 REV. E.
• P0731, P0732, P0733, P0734, P0735 — These are 'Incorrect Gear Ratio' codes for gears 1 through 5. They are triggered when the transmission slips due to incorrect pressure, a common symptom of the internal failure noted in the TSB.
• P0871 — This code relates to the 'Transmission Fluid Pressure Sensor/Switch 'C' Circuit'. Seeing it with P0841 can indicate a widespread hydraulic or electrical problem affecting multiple sensors, as seen in the TSB case.

Technical Service Bulletins (TSBs) & Recalls

• 21-012-25 REV. E: Lists P0841-00 as a key indicator of a cracking rear selective thrust bearing in certain 2024 Ram 2500/3500 trucks with the 68RFE transmission, requiring a full transmission replacement.

Platform-Specific Known Issues

• TSB 21-012-25 REV. E: This is the most critical issue. It identifies that 2024 Ram 2500/3500 trucks with the 68RFE transmission built between June 14, 2024, and September 04, 2024, can suffer from a cracking rear selective thrust bearing. This defect causes multiple pressure and gear ratio codes, including P0841, and requires a full transmission replacement.

Mechanic-Grade Diagnostic Values

• (T50) L/R Pressure Switch Sense Circuit Resistance to PCM — expected: Less than 5.0 Ohms. Failure: Resistance above 5.0 Ohms indicates an open circuit.
• (T50) L/R Pressure Switch Sense Circuit Resistance to Ground — expected: Greater than 5.0 Ohms. Failure: Resistance below 5.0 Ohms indicates a short to ground.
• Shift Solenoid Resistance (L/R, 2C, 4C, UD, OD) — expected: ~1.9 Ohms. Failure: Significant deviation from 1.9 Ohms indicates a faulty solenoid coil.
• Line Pressure Solenoid Resistance — expected: ~4.3 Ohms. Failure: Significant deviation from 4.3 Ohms indicates a faulty solenoid coil.
• Pressure Switch Operating Pressure — expected: Switches close at 23 PSI and open at 11 PSI.. Failure: Failure to switch within this pressure range indicates a faulty switch.
• Scan Tool Desired vs. Actual Line Pressure — expected: Actual pressure should closely track desired pressure. Minimum learned line pressure starts at 40 PSI.. Failure: A large discrepancy between desired and actual pressure points to a pressure control problem (pump, regulator, solenoid).

Scan Tool Commands That Help

• wiTECH or equivalent professional scan tool: Quick Learn Procedure — This function is required after replacing the valve body or solenoid pack to allow the TCM to learn the hydraulic and electronic characteristics of the new components. Failure to perform this can result in poor shift quality or fault codes.
• wiTECH 2.0 with Scandit App: Solenoid Characterization / PI Curve Programming — On 2019 and newer 68RFE transmissions, if the solenoid pack (specifically the TCC solenoid assembly) is replaced, a unique 46-character code must be programmed into the TCM. This code is generated by scanning a 2D barcode on the new solenoid. Swapping the original solenoid onto the new valve body can bypass this step.

Wiring & Ground Locations

• Transmission Harness Chafe Point — Along the frame rail, specifically noted by owners to be near the driver's side mudflap.. Vibration and road debris can cause the harness to rub through, creating a short or open in the L/R pressure switch circuit, directly causing a P0841 code even when the sensor is good.
• Transmission Solenoid/TRS Assembly Connector — Main electrical connector on the driver's side of the transmission case, connecting to the solenoid pack.. This is the primary connection for the L/R pressure switch. It is a known area for corrosion and debris intrusion, which can interrupt the signal and trigger the code.
• TCM (within NGC) — The Transmission Control Module is housed in the Next Generation Controller (NGC) located at the rear of the engine compartment, near the right inner fender.. This is the destination for the L/R pressure switch signal. All circuit tests terminate at the C1 and C4 connectors of this module.
• (T50) L/R Pressure Switch Sense Circuit — This is the specific electrical circuit running from the solenoid pack connector to the TCM.. This is the circuit that must be tested for continuity (ohms) and shorts to ground/power when diagnosing P0841 electrically.

Real Owner Repair Stories

• Reddit user in r/Cummins (68RFE, 112k miles, frequent towing) — P0841 code, hard/late shifting, no overdrive. Clearing the code makes it run normally for 10-15 miles.
  ❌ Tried (didn't work) Replaced the transmission pressure sensor, Replaced the entire valve body, Performed a transmission fluid and filter flush/change
  ✅ What actually fixed it The user was advised that the likely remaining causes were a wiring issue along the frame rail (specifically near the driver's side mudflap) or a faulty PCM, as the common parts had already been replaced without success.
• Turbo Diesel Register forum user (2008 Ram 2500 6.7L) — Initially P0868 and P0871, lunging. After parts replacement, went into limp mode (4th gear only) with code P0750, then intermittent limp mode (1st and 4th only) after further changes.
  ❌ Tried (didn't work) Replacing the valve body, Installing a 'rebuilt' solenoid pack, which was diagnosed as dead on arrival.
  ✅ What actually fixed it The issue was partially resolved by reinstalling the original solenoid pack (which the owner had personally rebuilt with new o-rings/plate) and a new pressure sensor. The story highlights the unreliability of some 'rebuilt' electronic parts, as the purchased rebuilt solenoid was faulty out of the box.
• RamForum.com user (2018 Ram 2500, 86,000 miles) — Truck would not go into gear after valve body replacement. A second attempt resulted in the PRNDL indicator being incorrect and the truck still not moving.
  ❌ Tried (didn't work) Installing a NextGen Drivetrain Billet Valve Body and new solenoid pack., Removing and reinstalling the new valve body three times to check for installation error (e.g., misaligned actuator arm).
  ✅ What actually fixed it The owner took the truck to a professional shop, which determined the brand new aftermarket valve body was faulty. The final fix was to return the aftermarket part and install a stock valve body.

"I Checked Everything" — The Actual Cause

• For code P0841, the equivalent of a 'smoke test clean' scenario is when the L/R pressure sensor and its wiring test perfectly for continuity and voltage, yet the code persists. In these cases, the root cause is often mechanical or a more subtle electronic failure. One specific example is a damaged or cut No. 1 check ball within the valve body, which would not be found with electrical tests. Another is a flexing circuit board on the solenoid pack, which can cause intermittent false pressure switch codes that are hard to trace.

When the Usual Fixes Don't Work

• While a faulty solenoid pack is a common cause for P0841 on trucks outside the TSB window, multiple owner accounts show that simply replacing this part is not a guaranteed fix. In one case, a brand new aftermarket valve body was faulty out of the box, and the problem was only resolved by reinstalling an OEM part. In another, after replacing both the sensor and valve body, the code remained, pointing towards a more elusive wiring harness issue along the frame rail. These stories serve as a strong counterpoint to simple 'parts-swapping' diagnostics and emphasize the need to test the entire circuit, from the sensor to the PCM, and to be wary of aftermarket electronic component quality.

OEM Part Supersession History

• 68353383AB (and many others) → 68353383AC — Standard part revision and consolidation by the manufacturer.
  Heads up: The part number for the main solenoid pack has been superseded multiple times. Previous numbers include 5170877aa, 52119435af, and 68353383ab. The current part is 68353383AC.
• White Connector Solenoid Pack (e.g., 2007.5-2010) → Gray Connector (2011-2018), Blue Connector (2019+) — Design changes by Chrysler/Ram over the transmission's production life.
  Heads up: While the older white connector pack is reported to be backward compatible with newer models (up to 2018), the gray connector pack (2011-2018) is NOT forward or backward compatible. The blue connector pack (2019+) is physically different and requires electronic programming (PI Curve) that older trucks cannot support.

Model Year Variations Within This Range

• 2024 (specific build dates): For 68RFE transmissions built between June 14, 2024, and September 04, 2024, code P0841 is a primary indicator of a catastrophic internal failure (cracked thrust bearing) requiring complete transmission replacement per TSB 21-012-25 REV. E.
• 2019-2024: Models from 2019 onward use a 'blue connector' solenoid pack with a different TCC solenoid design. Replacing this assembly requires a mandatory electronic programming procedure where a 46-character code from the new part is written to the TCM using a dealer-level scan tool. This procedure did not exist on pre-2019 models.

Diagnostic Flowchart

Other Known Issues on This Vehicle

Issues unrelated to this code that are worth knowing about as an owner of this generation:

• Emissions System Problems (DPF/EGR) 🔴 High — Common across all modern diesel trucks, especially those used for short trips. Issues include clogged DPFs and failing EGR coolers/valves.
• Variable Geometry Turbo (VGT) Actuator Failure 🟠 Medium — Soot buildup can cause the VGT actuator to stick or fail, typically at higher mileage (over 120,000 miles), leading to poor performance and check engine lights.
• Steering Column Control Module Fault 🟠 Medium — A recall was issued for some 2023-2024 models where the SCCM could cause high beams to activate with the turn signal, or vice-versa. (Ref: FCA US, LLC Recall #14B, 33B, 34B, 35B, 36B)
• Transfer Case Output Seal Leak 🟡 Low — Some owners have reported minor leaks from the transfer case output shaft seal, even at very low mileage.
• Heater Grid Bolt Failure 🔴 High — A well-known issue on 6.7L Cummins engines where the heater grid bolt can break off and fall into the engine, causing catastrophic damage. While rarer on newer models, it's a known potential failure.

Used vs. New Parts: Buying Guide for This Vehicle

When a used part is the smart pick: A used wiring harness from a donor vehicle in a dry climate can be a cost-effective fix if a chafe or corrosion issue is identified. A complete low-mileage valve body assembly might be considered, but it carries risks.

Donor-vehicle mileage cap: roughly under 60000 miles for the part to have meaningful remaining life.

What to inspect on the donor part:

• Check the donor vehicle's transmission pan for excessive metal shavings or burnt fluid before pulling the part.
• Inspect the main electrical connector on the part for any signs of corrosion (green crust), bent pins, or heat damage.
• If possible, get the VIN of the donor to ensure it's outside of any known TSB-affected build dates.

OEM-only on this vehicle (don't cheap out):

• Transmission Solenoid / TRS Assembly: Aftermarket and even 'rebuilt' solenoid packs have a documented high failure rate, with issues ranging from dead-on-arrival units to fatigued internal circuit boards causing intermittent faults. Sticking with a new Mopar part is strongly recommended to avoid repeat repairs.
• Automatic Transmission Fluid: Only Mopar ATF+4 or a licensed equivalent should be used. The 68RFE is sensitive to fluid chemistry, and using a generic fluid can cause shifting problems.

Aftermarket brands forum-validated for this vehicle:

• Sonnax: Widely regarded as the top choice for upgraded valve body components, including accumulator plates and switch valves designed to fix OEM weaknesses.
• SunCoast, RevMax, BD Diesel: Reputable names in the diesel performance world for complete rebuilt transmissions and upgraded valve bodies.

Brands owners have reported issues with on this vehicle:

• Unnamed 'rebuilt' solenoid packs: One owner reported a rebuilt unit was dead on arrival, causing significant diagnostic confusion.
• NextGen Drivetrain: A forum user reported receiving a faulty billet valve body that caused a no-shift condition, requiring a return to a stock part.

Real Owner Stories

Aggregated from forums and TSBs cited above. Mileages and costs reflect what owners reported in those sources.

Related OBD-II Codes

• P0868 — Transmission Fluid Pressure Low; often appears alongside P0841 in cases of internal failure or low fluid.
• P0944 — Loss Of Hydraulic Pump Prime; cited in TSB 21-012-25 REV. E as a companion code for the cracked thrust bearing issue.
• P0730 — Incorrect Gear Ratio; these 'P073x' codes frequently accompany P0841 when internal mechanical damage prevents proper gear engagement.
• P0935 — Hydraulic Pressure Sensor High; discussed in forum contexts as a related electrical fault within the transmission pressure circuit.

Frequently Asked Questions