Case IH 19527 – Engine Control Module (ECM) / EDC (Electronic Diesel Control): DPF Lube Oil monitoring: Fuel in oil has exceeded the limit for safe driveability

Severe fuel dilution in the engine crankcase. Unburned fuel from frequent, incomplete, or prolonged DPF regenerations washes past the piston rings and accumulates in the oil pan, causing oil viscosity to drop dangerously low.

• Tier 4b
• Farmall 115C
• Farmall 120C
• Magnum 235
• Magnum 280
• WD2504
• TR310
• CX-series excavators

1. 1

   Check the Dipstick: Pull the engine oil dipstick. The oil level will likely read significantly overfull, and the oil will have a distinct diesel fuel odor and a thin, watery consistency.

2. 2

   Check for Accompanying Codes: Look for other active codes that point to the root cause of the frequent regenerations. Check for DPF restriction/soot load codes, exhaust temperature sensor faults, or fuel system codes (e.g., 3635, 3636, 3637 which also relate to fuel-in-oil/rail pressure drops).

3. 3

   Inspect Fuel System Components: While DPF regeneration is the most common cause, fuel dilution can also be caused by a leaking fuel injector or a leaking seal on the high-pressure fuel pump (CP3).

4. 4

   Review Regeneration History: Use the diagnostic tool to check how often the DPF has been regenerating. If the filter is heavily loaded, it must be addressed to prevent the new oil from being diluted immediately.

1. 1

   Drain the Contaminated Oil

   Safely drain the fuel-diluted engine oil from the crankcase.

2. 2

   Replace the Filter

   Remove and replace the engine oil filter.

3. 3

   Refill Engine Oil

   Refill the engine with the correct capacity of fresh, DPF-compatible Low-SAPS engine oil (typically 15W-40 CJ-4 or CK-4).

4. 4

   Reset the ECU Counter

   Connect the CNH Electronic Service Tool (EST) laptop to the machine's diagnostic port. Navigate to the Engine Controller (EDC) and perform the Oil Dilution Reset / Oil Change Reset procedure. Note: If you only change the oil without resetting the software counter, the ECU will still believe the oil is diluted and the code will remain active.

5. 5

   Clear Fault Codes

   Clear code 19527 and any related historical codes.

6. 6

   Perform a Manual Regeneration

   Initiate a parked/forced DPF regeneration using the EST to clear out any accumulated soot and verify that the exhaust temperature sensors and dosing system are operating correctly.