91 Expo 4 wheel not disengaging

[The Lt.]

Well I will try to make this short...maybe somone can help me out...
We locked the hubs in then hit the 4x4 button...all good.
Went through a little mud got stuck pulled it out...all good
Hit the 4x4 button to go back to 2 high...not all good It will not unlock. We unlock the hubs and it will not give power top the front tires...however the T-case is still in 4 wheel drive...how do we get it back into 2 high?
Dan

 

[BrianDye]

reset the 4wd module, have the truck running, or the key on, and goto the back compartment where the little jack is, and in front of the washer fluid, towards the seats, theres a module, and its the 4x4, theres a little white button, press and hold that for a few seconds, then go turn your key off and back on, if the red lights still on, press the button again and you're all good, if the lights not on your all good, you might have to press the 4x4 button once more

hope this helps

 

[The Lt.]

ok i am going to go and try this...

 

[The Lt.]

Did not work...any other ideas?

 

[BrianDye]

hmm, i would say try to like disconnect the power going to the 4x4 under the truck, but im not sure how to do that, the next thing id try, is disconnect the negative battery terminal, then turn the key over to start it (just to get any bit of power still in there, out)

 

[MrShorty]

So the hubs unlocked just fine?

For a short while, when I had mismatched tires (all same size but different manufacturer), my BII had a hard time disengaging the 4wd (manual hubs/t-case) from the tension that built up in the drivetrain from the slightly different tire sizes. Not sure that this applies to your situation if the hubs unlock easily.

The other thought I have is maybe the shift motor is dirty. You might try tapping the motor with a hammer or something to see if that frees up the motor enough to get it to move. You could also try taking the shift motor off and see if it shifts easily by hand.

 

[The Lt.]

Surly a few good suggestions...we are going to have to take a look into them...I will let everyone know how all that go's.
Dan

 

[DeRocha]

I assume you have already taken a peek at the 4x4 troubleshooting thread correct?

I assume you are stuck in 4H and not 4L correct?

At least with manual hubs set to Unlock you can still run with the T-Case in 4x4 for street use to get home.. It does sound as if the shift motor may need a little coaxing to get it to shift back into 4x2.. As mentioned in the previous post if there is too much stress on the driveline the shift motor may not have enough power to shift it out of 4x4. Turning the hubs to "FREE" and on level ground the 4x4 button should work easily.