91 Ranger, odd process to engage 4wd

[Dddaviso7]

As the title says, I have to go through a rather weird process to engage 4wd.

I recently bought this 91 2.9l 4x4 Ranger for my winter beater. It has the automatic hubs and transfer case (which are 2 things I was trying to avoid, but the price was soooooo right). In order to get the truck to lock into 4x4, This is the process.

Select 4x4. Shift to neutral/hold brake, engage 4lo. Drive for a few feet. Back into neutral/hold brake, disengage 4lo. Then the 4hi stays engaged.

And as usual with these push button Tcases, Sometimes i can hit the buttons and nothing happens at all.

If I just push the 4x4 button and drive on, The light comes on, you hear the shift motor do its thing, but the front doesn't lock in. Not sure if it's related but there is a squeaking noise that gets faster as you go faster, i've had several people on the outside/inside of the vehicle trying to help pinpoint it, The consensus is "the front".

I did some research and came up with a ton of results but nothing exactly like my issue. Any one have an idea? I was assuming its a hub issue, but then why would 4lo make it work?

 

[4x4junkie]

If I was going to guess, I would say the sensor cover on the rear of the shift motor gear housing might be misaligned just a slight bit (there are no detents to index it, it's just held in place by the 3 rear screws). This would cause the motor to align the shift mechanism "off" just a little when it completes the shift (going to 4-lo and back again is probably just enough to get 4-hi to stay engaged).

Not sure if the squeaking is related or not... Is the squeaking present while in 4-Lo?

 

[Dddaviso7]

Thank you, I'll have to take a look at that sensor cover. Auto transfer cases are completely new to me. I've only had manuals in the past.

The squeak is there regardless of 2wd/4wd.

 

[ab_slack]

If I were to guess I would think the squeak is a different issue than the shift in/out problem.

Even though the hubs aren't locking if I understand in 4hi, if the transfer case has shifted into 4hi, the front end shaft is going to spin (just like it will when hubs are locked) and shafts from front diff to the wheels are going to move tho if hubs aren't locked those shafts probably won't be turning the same. Anyways, with hubs locked or just 4WD engaged there is going to be stuff up there moving with potential of making noise.