Ford 2003 Mustang Workshop Manual page 320

installation.
8. Using the special tool, remove the pinion flange.
Installation
1. Inspect the pinion flange seal journal for rust, nicks, and scratches prior to installing the flange.
Polish the seal journal with fine crocus cloth, if necessary.
2. Lubricate the pinion flange splines.
Use SAE 80W-90 Premium Rear Axle Lubricant XY-80W90-QL or equivalent meeting
Ford specification WSP-M2C197-A.
3. NOTE: Disregard the index marks if installing a new pinion flange.
Position the pinion flange.
4. Using the special tools, install the pinion flange.