Ford 2003 Mustang Workshop Manual page 324

3. NOTE: If possible, allow one hour before filling the axle with lubricant to make sure the silicone
sealant has cured.
Install the differential housing cover.
1. Install the differential housing cover.
2. Install the 10 bolts.
4. NOTE: In-vehicle repair refill capacities are determined by filling the rear axle with the specified
lubricant to 6.4-14.3-mm (1/4-9/16-in) below the bottom of the fill hole.
Fill the rear axle to the level shown, approximately 1.54-1.66-liters (3.25-3.50-pints) of lubricant,
and install the filler plug.
Use SAE 80W-90 Premium Rear Axle Lubricant XY-80W90-QL or equivalent meeting
Ford specification WSP-M2C197-A.
5. Lower the vehicle.