Some 2021-2022 Explorer - Timberline - vehicles may exhibit a rear differential that is venting rear axle fluid. This may result in a noise, odor, or leak noticed by the customer. Inspect the rear of the vehicle for signs of rear differential fluid venting into the rear wheel well, or leaking from the rear differential. If signs of fluid leaks are found from any seals, repair as necessary per Workshop Manual Section 205-02. If no seal leaks are found but fluid is venting, drain the rear differential. Add 85-100 ml of Motorcraft® XL-3 Additive Friction Modifier. Refill with fresh rear differential fluid to bottom of fill plug. Remove the vent tube and use compressed air to verify that the fluid vent tube is clear, then reinstall tube. Engineering investigating, monitor OASIS for updates.
