Ford 9L1Z-4K138-A Shaft Assembly

If the vehicle is equipped with air suspension, turn off the air suspension system. The switch is located behind the right kick panel. Raise the rear of the vehicle, support it securely on jackstands and block the front wheels. Remove the wheel and brake drum or disc. Remove the cover from the differential carrier and allow the lubricant to drain into a container. Remove the lock bolt from the differential pinion shaft. Slide the notched end of the pinion shaft out of the differential case as far as it will go. Position a large screwdriver between the rear axle case and a ring gear bolt to keep the differential case from turning when removing the pinion shaft lock bolt. Rotate the differential case 180-degrees and slide the pinion shaft out of the case until the stepped part of the shaft contacts the ring gear. Push the outer (flanged) end of the axleshaft in and remove the C-lock from the inner end of the shaft. Withdraw the axleshaft, taking care not to damage the oil seal in the end of the axle housing as the splined end of the axleshaft passes through it. Installation is the reverse of removal. The manufacturer recommends that a new pinion shaft lock bolt be used, but if one is not available, coat the threads with a non-hardening thread locking compound. Install the pinion shaft lock bolt and tighten it. Install the differential cover. Install the brake drum or disc/caliper. Refill the axle with the correct quantity and grade of lubricant. Tighten the wheel lug nuts.

Disconnect the vacuum lines.

For installation, follow the reverse order of removal, ensuring proper tightening of the driveaxle hub nut and CV joint flange bolts. Use a new cotter pin and reactivate the air suspension system if applicable.