Inspection After Removal

WARNING: This page is about a different car, the 2018 Nissan Titan XD. However, it is still accessible from the selected car via links, so may be relevant.

Clean and inspect the oil thermostat bore in the front cover before assembly.
Inspect for a damaged O-ring, broken spring, or other damage.
If damage is found, the component must be replaced.

OIL THERMOSTAT TEST

Suspend the oil thermostat (1) and a thermometer (capable of at least 116°C [240°F]) in a container of new engine oil. Do not allow the oil thermostat to contact the sides of the container.

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Heat the lubricating oil.
NOTE: Note the temperature when the thermostat valve is fully expanded. The oil thermostat should not be fully expanded when the temperature reaches 116°C (240°F).
Replace the oil thermostat if it does not operate as described.