Section 2.1
Improper Engine Oil Level

To determine if improper engine oil level is causing low oil pressure, perform the following steps: ‪

1. Ensure that the vehicle is parked on level ground.
2. Check the engine oil level; refer to appropriate service manual, preventive maintenance chapter.
   1. If the engine oil level is correct, check lubricating oil viscosity; refer to "2.2 Improper Lubricating Oil Viscosity" .
   2. If the engine oil level is incorrect, fill engine oil pan to correct level; refer to appropriate service manual, preventive maintenance chapter.
3. Verify low engine oil resolution; refer to .

Section 2.1.1
Test for Proper Engine Oil Level

Perform the following steps to determine if properly filled oil pan resolved low oil pressure:‪

1. Connect Detroit Diesel Diagnostic Link (DDDL 7.0) to check the oil pressure.
2. Start and vary engine speed between 1800 - 2100 rpm.
3. Check DDDL 7.0 for oil pressure reading.
   1. If DDDL 7.0 indicates oil pressure greater than or equal 241 kPa (35 psi) at 1800 rpm, shut down the engine and disconnect DDDL 7.0. Refer to "6 Excessive Oil Consumption" to diagnose the cause for the low oil level.
   2. If DDDL 7.0 indicates oil pressure less than 241 kPa (35 psi), at 1800 rpm, shut down the engine and disconnect DDDL 7.0. Check oil pressure using a mechanical gage; refer to "2.1.2 Check Oil Pressure with a Mechanical Gauge" .

Section 2.1.2
Check Oil Pressure with a Mechanical Gauge

Check as follows:‪

1. Remove the oil pressure sending unit from the engine.
2. Connect a mechanical oil pressure gage to oil pressure sending unit port on the engine.
3. Start the engine. Verify that the engine speed is between 1800 and 2100 rpm.
   1. If the oil pressure is greater than or equal to 241 kpa (35 psi), refer to "2.4 Faulty Oil Pressure Gauge Sensor" .
   2. If oil pressure is less than 241 kpa (35 psi),refer to "2.2 Improper Lubricating Oil Viscosity" .