Help, transfer case locked up in 4wd

[mikepier]

Hi all, original owner of 1999 XLT SOHC, 190K miles,
Yesterday all of a sudden, the truck does not want to move when making turns.
My first thought was the transfer case is locked up.
Disconnected electrical connections to the TC motor , but still locked up.
I then removed the front driveshaft and now all is well. Does this mean my transfer case is toast?
I changed the fluid in an attempt to hopefully flush contaminants out. I’ll drive around for a bit and see if it hopefully un-locks it, but in the event this doesn’t fix it , is the only choice to get another transfer case?
Also is it safe to drive without the front driveshaft ? I heard rumors the car can drift in park but from what I can tell, the truck doesn’t move when I put in park.

 

[imp]

Hi all, original owner of 1999 XLT SOHC, 190K miles,
Yesterday all of a sudden, the truck does not want to move when making turns.
My first thought was the transfer case is locked up.
Disconnected electrical connections to the TC motor , but still locked up.
I then removed the front driveshaft and now all is well. Does this mean my transfer case is toast?
I changed the fluid in an attempt to hopefully flush contaminants out. I’ll drive around for a bit and see if it hopefully un-locks it, but in the event this doesn’t fix it , is the only choice to get another transfer case?
Also is it safe to drive without the front driveshaft ? I heard rumors the car can drift in park but from what I can tell, the truck doesn’t move when I put in park.

@mikepier
If not AWD, no drift in park. No problem without front driveshaft. If no noise was being made by the transfer case, it likely is not busted. Possible causes are locked-up Electronic Clutch, or broken/jammed shift parts in T-case, any of which is fixable. imp

 

[masospaghetti]

Only the AWD models drift in park due to the viscous coupling in the BW 4404. The TC motor only controls 4x4 Low, so disconnecting doesn't make any difference in your case.

The 4x4 High function is controlled by an electronic clutch inside the TC. Not sure if there's a fuse for it? Maybe it's stuck "on"?

You might also try jacking up the vehicle and verifying that the TC is locked by spinning the front wheels.

 

[rasouth]

I had my TC lock up on me like that once. I was told to make sure it was in 2WD and and put it in reverse and drive backwards and forwards a short distance. My TC unlocked and no problems since.
Rebuilding the TC is not a hard project if you can get it out. I did mine a couple years ago and it did not cost much for a shift fork and pads.

 

[mikepier]

I did a test. I had my son put the truck in neutral with truck off, and he let truck slowly roll while I observed the front output shaft of the TC, and it was still turning, (with front driveshaft removed) so I’m guessing that rules out the electronic clutch since it’s not energized.
It looks like it’s mechanically stuck inside the TC.
I’ll try driving around a bit, see if it can free itself.

 

[410Fortune]

Silly question but have you unbolted the t case shift motor to see what gear the t case is in? If it is in 4hi then maybe you just need to fix the shifting (shift motor)

 

[mikepier]

Yes I did and it is in 4 high but from what I read that is the normal position correct?

The only other two positions is 4 low and neutral.

From what I read , 4hi only gets engaged through the electromagnetic sensors when slippage is detected , or by permanently putting it into 4 high on the dash switch.

 

[410Fortune]

I am 99.9% sure your t case has 3 positions:

2wd N 4hi 4low

seems like your shift motor failed to bring it back into 2wd....pretty common and would explain why you are in 4wd all the time

 

[imp]

I am 99.9% sure your t case has 3 positions:

2wd N 4hi 4low

seems like your shift motor failed to bring it back into 2wd....pretty common and would explain why you are in 4wd all the time

@410Fortune
I have forgotten the certainty, but seems my Ex with 4X4 AUTO, 4X4 HIGH, and 4X4 LOW switch positions on the dashboard had NO 2WD position indicated for the TC motor, only HIGH N and LOW.
See: Transfer case shaft "clock" position

 

[410Fortune]

thank you! I cannot believe I did not know this.....friggin wild.
I hate the control trac AWD so that is probably why...I just remove them and set them aside install something else

I love to learn new things, so thank you very much!!
Selective memory I guess just like "husband hearing"