97 4wd problem with front wheels engaging

[ssarkees]

Dont confuse this with a 95 which has a Vacuum Solenoid on the font axle -

I have a 97 - when I switch to 4H (electronic) or 4L the transfer case engages but the front wheels dont. (example - I put it in 4L and it goes into Low Gear, but the front wheels dont lock). I thought it might be the GEM, located in the dash, but if it were, I figured it would not even switch the transfer case.
Thanks in advance - Steve S.

 

[Opera House]

I assume you have Control Trac. Not sure what you mean by not engaging. This is a clutch in fluid and it doesn't "engage" unless it is moving. The magnetic field puts a drag on a rotating disk that allows three balls to climb a ramp and put pressure on the clutch plates. I don't think you would feel anything by just jacking it up and rotating a wheel. If you think you have an electrical problem, the clutch coil is about 3 ohms and draws from 1/4 to 3A.

 

[ssarkees]

Not engaging - the front wheels never lock into 4wd.
Where is this "clutch coil" located? is it on the transfer case?

 

[Opera House]

The 4405 transfer case has a single brown wire out of the back of the case. Search for "brown wire mod" for other useful information. I should have been more specific. What test or situation indicates the front wheels are not engaging.

 

[ssarkees]

I put it in neutral then switch to 4L (while stopped of course) then I put it in drive - I hear the transfercase zip into Low (and feel the lower gear diference) and while on dirt or mud, only the rear wheels will spin. Same goes for 4H. Only in 4H, I can be driving at regular speeds. I first noticed this when towing on grass - I put it in 4H and my rear wheels spun. The front wheels never locked in. I also noticed it while taking off on wet pavement - It is 4wd auto, so if the rear slips, the front pop in to help out. It stopped doing that. I went to a parts yard and got a transfer case motor and a new GEM (used), but have not put them in yet.
Thanks again

 

[TPLYNCH]

You may have broken the output shaft from the t/f case to the front diffy. If you feel the case engage, and you have the lower gearing, the GEM and case are doing their jobs. Its the output shaft that's shop

 

[Opera House]

The 4WD motor in the 4405 only shifts into HI, LO or NEUTRAL (yes, a Ford option can geive you that). It does not shift you into four wheel, that is done by the clutch. Replacing the GEM could possibly give you that. I've heard of some problems with the rolling ball clutch. These cases aren't hard to work on, but rebuild kits don't give you any clutch parts!!!!!!! I'd look for continuity of the "brown wire" down to to the transfer case.