New Holland ENG 3728 – Engine Control Unit (ECU) / EDC (Electronic Diesel Control): Engine Oil: Too Low Oil Viscosity

Engine oil viscosity breaks down and falls below a secondary safety threshold. This breakdown is typically caused by fuel or soot contaminating the engine oil, or simply by exceeding the oil's service life.

• L220
• L223
• L225
• L230
• SR175
• SR200
• SR250
• SV250
• TR270
• T4
• T5
• T6
• T7
• T8
• T9
• T4000
• T4020
• T4030
• T4040
• T4050
• TD5030
• W50C
• W60C
• W70C
• W80C
• CR9090
• CX8080
• CX8090

1. 1

   Check for Contamination Codes: Check the EDC for related active or stored fault codes. Codes 3726 and 3729 indicate fuel in oil detection, while code 3730 indicates soot in oil detection. If present, diagnose the fuel system or DPF/emissions system first.

2. 2

   Physical Inspection: Check the oil dipstick for overfilling (a strong indicator of fuel dilution) and smell the oil for diesel fuel.

1. 1

   Warm up engine

   Warm up the engine slightly to help the oil flow, then shut it down.

2. 2

   Drain oil

   Drain the degraded engine oil completely from the oil pan.

3. 3

   Replace oil filter

   Remove and replace the engine oil filter.

4. 4

   Refill engine oil

   Refill the engine with fresh, OEM-approved engine oil (typically 15W-40 meeting CNH MAT 3571 or MAT 3572 specifications) to the correct capacity.

5. 5

   Clear fault codes

   Connect a diagnostic tool to the machine's CAN-bus port and clear the active/stored fault codes from the Engine ECU (EDC).

6. 6

   Verify repair

   Run the engine, check for leaks, and verify the code does not return.