4x4 ISSUES, HELP!!!

Nathanialson 08

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Anybody know anything about the automatic locking hub's on the 3rd gen expeditions? the auto hub's on my 2008 Expy wont disengage from 4x4 mode, luckly I can still drive in 4x4 auto but i'm stumped at the moment and as my gas mizer car is having fuel issues this expy is my only working vehicles I have at the moment, any knowledge on how these work or how to fix it would be appreciated.
 
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mindgame

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You have a vacuum leak to the auto locking hubs... When a vacuum is present, the hubs are pulled away from the spindles. When no vacuum is present, hubs become engauged..

So either your IWE solenoid needs replacing (~$40), or one of your tubings to the hubs is loose or cracked..

:)
 
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Nathanialson 08

Nathanialson 08

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we called the Ford dealer and they told us the 3rd gens don't have vacuum system on the atuo locking hubs and thats its all electronicly powered, they changed the design for 2007, they said they can't disclose any more info for liability issues unless we pay them $95 to look at it and all we wanted to know is how they work not how to fix it.

WHAT ITS DOING- when I drive in 2wd mode the right front vibrates bad and you hear a growling sound, my Dad jacked the front of my truck up and crawled underneith and tried turning the front driveline and it wont budge, in 2wd mode it should be able to move with your bare hands but dosen't, now when you lock it into 4x4 high and AWD the sound and the vibration goes away.
 
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RI-Matt

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According to the service manual:

Four Wheel Drive (4WD) Systems
The 1-speed torque on demand (TOD) (Navigator) and 2-speed TOD (Expedition) four wheel drive (4WD) systems consist of the following:

•4WD mode select switch (MSS)
•4X4 control module
•Integrated wheel ends (IWEs) solenoid
•IWEs
•4WD mode indicators and messages in the instrument cluster (IC) message center
•Transfer case assembly
•Transfer case shift motor
•Steering wheel angle (SWA) signal from ABS module via high-speed controller area network (HS-CAN)
•Accelerator pedal position output from the PCM via HS-CAN
•Wheel speed signals from the ABS via HS-CAN


Integrated Wheel End (IWE) System

The IWE system contains the following:

•Vacuum reservoir
•IWE solenoid
•IWEs (spring loaded vacuum hubs)
•Vacuum hoses
•Check valve
The IWE system uses vacuum hubs that engage the front wheel hubs to the front halfshafts or disengage the front wheel hubs from the front halfshafts.

The IWE solenoid receives engine vacuum from the vacuum reservoir.

When the 4WD system is in two wheel drive (2WD) mode, the 4X4 control module supplies a ground path to the IWE solenoid to apply vacuum to the IWEs (disengaging the front hubs from the front halfshafts). In 4WD mode, the 4X4 control module does not supply the ground path to the IWE solenoid, vacuum is not applied to the IWEs and an internal spring keeps the front hubs engaged to the front halfshafts.




Matt
 

RI-Matt

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tonydiv

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Apparently, if just a little bit of water gets past the seal on those IWEs, they can rust up and stop operating.
 

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