Axle Fluid Analysis

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 appearance of milky or gray axle fluid can also be caused due to water contamination. The milky fluid appearance will diminish and cause no harm and does not require a fluid change. If internal axle damage is suspected and milky fluid is discovered upon inspection, the possible root cause can be water contamination. In this case identify the root cause of water contamination, replace the fluid and repair any related damage.