W126 drive shaft carrier/center bearing.
MARK THE DRIVE SHAFT FOR RE-ASSEMBLY, BEFORE SEPARATING THE SLIP JOINT...
The rubber carrier boot can be replaced without disturbing the bearing.
#1. Mark the alignment/orientation of the drive shaft assembly before separation !!!
WARNING:
Scratch a mark that can NOT be wiped away, then you can use a paint pen to enhance it.
#2. Loosen the slip joint nut.
#3. Separate the slip joint.
#4. Set aside the Rear section of the drive shaft.
#5. Mount the Front section of the drive shaft in a vise.
#6. Remove and clean the slip joint nut.
#7. Install the new slip joint nut boot.
#8. Clean and lubricate the internal slip joint splines with axle grease.
#9. Set aside the Front section of the drive shaft.
#5. Mount the Rear section of the drive shaft in a vise.
#6A Type one: Remove the snap ring.
#6B Type two: This type of pressed on debris cap has an internal lip on the outer face, and must be removed to access the carrier/center bearing snap ring = pry off cap and remove the snap ring.
#7. Press or knock the bad bearing off the drive shaft.
#8. Remove the rear debris cap.
#9. Install the new rear debris cap.
#10. Press or carefully hammer the new bearing on to the drive shaft, (drive only on the edge of the inner bearing race).
#11A Type one: Install new front debris cap and snap ring.
#11B Type two: Install the snap ring, then pressed on the new debris cap.
#12.
Instal the new rubber carrier boot.
#13. Install the slip joint nut with new boot on the spline shaft.
#14. Verify the internal and external slip joint splines have been cleaned and lubricated with axle grease.
#15. Pick up the Front section of the drive shaft.
#16. Re-assemble front and rear sections by matching the alignment/orientation marks of the drive shaft assembly.
#17. Hand tighten the slip joint nut, (final tightening MUST be with the drive shaft mounted in the vehicle).
Here is a related DIY LINK.
Driveshaft, Axle & Wheel bearing
http://www.peachparts.com/shopforum/showthread.php?t=142402
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