4X4 WHEEL HUB NON-ENGAGEMENT/DISENGAGEMENT
TECHNICAL SERVICE BULLETIN
Reference Number(s): 03-14-3, Date of Issue: July 21, 2003
FORD:2000-2003 EXCURSION, SUPER DUTY F SERIES
Related Ref Number(s): 03-14-3
SUSPENSION - 4X4 WHEEL HUB NON-ENGAGEMENT/DISENGAGEMENT
AXLE - 4X4 WHEEL HUB NON-ENGAGEMENT/DISENGAGEMENT
Some 2000-2003 F-250/350 and Excursion 4X4 equipped vehicles may experience a condition where the front hubs will not engage or disengage properly. It is possible that the vacuum necessary to operate the hub is being restricted.
Insure that the flow of vacuum is not being restricted through the hub. Perform Workshop Manual diagnosis per Section 308-07-A Pin Point Test G. If no problems are found in Pin Point Test G, perform the following procedure to relieve restriction in the vacuum path through the wheel end.
Remove both wheel hub assemblies (See WHEEL HUB removal procedure under Section 204-01B: FRONT SUSPENSION).
Remove thrust washer located between the wheel hub assembly and the axle constant shaft (This gray plastic thrust washer is approximately 2 3/4" OD, and has four slots on the back side).
NOTE:KNUCKLE SEAL DOES NOT NEED TO BE REPLACED FOR THIS PROCEDURE.
File four (4) 1/8" to 1/4" "KEYWAYS" into the inside diameter of the thrust washer (Fig. 1 ).
NOTE:THE THRUST WASHER REQUIRES ONLY A LIGHT FILM OF GREASE. REMOVE ANY EXCESSIVE GREASE FROM WASHER, AND CAVITY BEFORE INSTALLATION.
NOTE:THE ADDITION OF THE KEYWAYS AND THE REMOVAL OF EXCESSIVE GREASE WILL ALLOW VACUUM TO PASS, UNRESTRICTED, FROM THE KNUCKLE, THROUGH THE HUB, AND TO THE HUB LOCK.
Reassemble wheel end per Workshop Manual Section 204-01B.
NOTE:DURING RE-ASSEMBLY, REPLACE YELLOW BEARING O-RING WITH PART NUMBER F81Z-4A322-AA. REPLACE HUBLOCK O-RING WITH PART NUMBER F81Z-1K106-AA. THE O-RINGS ARE CRUCIAL FOR PROPER VACUUM SEQUENCE OPERATION AND FUNCTION OF THE HUBLOCK.
Part NumberPart Name
F81Z-4A322-AAO-Ring - Bearing
F81Z-1K106-AAO-Ring - Hublock
WARRANTY STATUS: Information Only.
Tuesday, December 2nd, 2008 AT 6:13 PM