4X4 System - Front Hubs Won't Lock/Disengage
TSB 04-18-509/20/04
AXLE - FRONT HUBS NOT ENGAGING, NOT STAYING ENGAGED AND/OR UNLOCKING
FORD:
1999-2004 F-SUPER DUTY
2000-2004 EXCURSION
This article supersedes TSB 04-11-6 to update the vehicle lines listed in the printed version of TSB 04-11-6.
ISSUE
Some 4X4 vehicles may exhibit a hub not engaging, not staying engaged and/or unlocking. This may be due to hub lock damage caused by contact between the front axle shaft and the inside of the hub lock assembly.
ACTION
Follow normal Workshop Manual diagnostics for four wheel drive system. If diagnostics lead to a failed hub lock, check the inside of the hub lock for signs of contact with the axle shaft (Figure 1). If signs of contact are evident, perform the following procedure when replacing the hub lock assembly.
SERVICE PROCEDURE
1. Remove the hub lock assembly. Refer to Workshop Manual Section 308-07A (for 1999 model year vehicles refer to 2000 Workshop Manual).
2. Insert clean rag into wheel hub cavity to protect it from contamination.
3. Drill out axle shaft pilot hole to 16 mm (5/8") diameter and 2 mm (0.08") deep (Figure 2). The axle shaft does not need to be removed from wheel-end assembly for this step.
NOTE
OPENING THE SHAFT PILOT HOLE DIAMETER WILL PROVIDE CLEARANCE TO THE METAL TABS, LOCATED INSIDE THE HUB LOCK, DURING ENGAGEMENT CYCLING.
4. Remove all contaminants from hub cavity and reassemble.
PARTS BLOCK
WARRANTY STATUS:
Eligible Under Provisions Of New Vehicle Limited Warranty Coverage
OPERATION DESCRIPTION TIME
041805A Replace Hub 0.3 Hr
Lock Assembly
And Drill Axle
Shaft Pilot Hole
(Does Not Include
Time For The Diagnosis
Described In The
Repair Action) One
Hub
041805B Replace Hub 0.5 Hr.
Lock Assembly
And Drill Axle
Shaft Pilot Hole
(Does Not Include
Time For The
Diagnosis Described
In The Repair Action)
Both Hubs
DEALER CODING
CONDITION
BASIC PART NO. CODE
3B396 07
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