Axle Fluid Analysis
WARNING: This page is about a different car, the 2022 Ford Ranger. However, it is still accessible from the selected car via links, so may be relevant.
The appearance of milky or gray axle fluid in early mileage axles is a result of white marking compound used at the assembly plant to verify gear mesh contact pattern. The marking compound within the fluid will darken some over time. The milky fluid appearance will diminish and cause no harm and does not require a fluid change.