Engine oil temperature transient is specified as?

Engine oil temperature transient is specified as?

• A. 127 °C (5 min with N1 at 61+-1%)
• B. 125 °C (5 min with N1 at 60±1%)
• C. 130 °C (5 min with N1 at 62±1%)
• D. 120 °C (5 min with N1 at 61±1%)

Answer: (A)

Engine oil temperature transient defines a safe upper limit the oil can reach during a controlled warm-up transient, with the engine held at a specific N1 level so the test is reproducible. The standard specification used here is 127 °C for 5 minutes while N1 is around 61% (±1%). This pairing is chosen to represent a realistic transient that stresses the lubrication system without driving the oil into regimes where viscosity would drop too much or component wear would rise, and the 5-minute duration ensures the limit applies to a sustained transient rather than a short spike. The other options set different temperatures (lower or higher) or a slightly different N1 target, which wouldn’t match the defined transient condition.

Engine oil temperature transient defines a safe upper limit the oil can reach during a controlled warm-up transient, with the engine held at a specific N1 level so the test is reproducible. The standard specification used here is 127 °C for 5 minutes while N1 is around 61% (±1%). This pairing is chosen to represent a realistic transient that stresses the lubrication system without driving the oil into regimes where viscosity would drop too much or component wear would rise, and the 5-minute duration ensures the limit applies to a sustained transient rather than a short spike. The other options set different temperatures (lower or higher) or a slightly different N1 target, which wouldn’t match the defined transient condition.