1997 XLT stuck in 4wd low?

[LuLu71730]

When trying to manually disengage (with a pair of pliers) the 4wd how far are you supposed to turn the the shift knob? Is it supposed to spring back? Or do you keep turning until it "clunks" and stays in a position?

 

[LuLu71730]

Let me explain, maybe I can get a suggestion.....

I just bought a 1997 XLT, the person I bought it from said it needed a shift motor because it was stuck in 4wd hi. When I drove it, it shifted quickly and I could only get up to 30mph so I am thinking it is stuck in 4wd low. The OD light was flashing and sometimes both 4wd and 4wd low lights flash. After getting it home, we played with it a bit, switching it in and out of 4wd. While in neutral with the brake pedal depressed and in the “auto” position I switched it to 4wd hi, the 4wd light came on but nothing else happened so I then switched it to 4wd low and heard a clicking noise coming from behind the radio but the 4wd low light does not come on. We have jacked it up and confirmed the front is not locked in 4wd. We also took the shift motor off the transfer case and tried to manually shift it to 2wd but the shaft spins back every time we let go. How much or how far do you need to turn it? After reinstalling the shift motor and turning the switch from auto to 4wd the shift motor makes a sound and then I turned it to 4wd low and heard the same clicking noise behind the radio and also heard the shift motor making the noise again but it is still doing the same thing. I now think it maybe something in the TC, are we “thinking” in the right direction??? Any suggestions????

 

[IZwack]

Frist read http://www.explorerforum.com/forums/showthread.php?t=203441

 

[ledzeppelin166]

When trying to manually disengage (with a pair of pliers) the 4wd how far are you supposed to turn the the shift knob? Is it supposed to spring back? Or do you keep turning until it "clunks" and stays in a position?

i know on the first gen explorers that it will lock in and it will spring back if you dont turn it far enough. if its in 4 low then you gotta turn it to 4 high then to 2 high. but mine might be different then yours.

 

[LuLu71730]

The front drive shaft turns in all positions, Auto, hi, and low, it is not engaging...... so it is NOT because of the shift motor. It has been drove on the highway like this so it could be the Transfer Case Clutch????

If you select 4 low, the transfer case remains locked, but engages a set of planetary gears to obtain the low range gear reduction. The front and rear driveshafts are still linked solely by the Transfer Case Clutch. By interrupting the power flow to the TCCC when in 4 low, the transfer case disengages the front driveshaft, even though the planetary reduction gears are engaged. This results in a true 2wd low range.

I have power to the brown wire at the TC, could the planetary reduction gears still be engaged, how would I check this?

Sorry for my stupidity, I am new to the "electric" 4wd drive systems and have read so much I am confused about everything...

 

[IZwack]

Okay pop the shift motor out and see where the shift rod is pointing to -- I think in your transfer case, you should see "AUTO" or "4L".

 

[LuLu71730]

4l

 

[IZwack]

Okay so the transfer case is doing its job, the problem is purely electrical.

This is going to sound odd but it has worked a few times to some users on here -- park the vehicle, rotate the transfer case switch on the dashboard to the AUTO position, and disconnect the battery for about 10 mins. Then reconnect it and take the vehicle for a spin and see if the transfer case is still in 4LO -- if its not, the RPMs should be a lot lower than when it was stuck in 4LO.

My suggestion is to never use 4LO (4HI is fine), it only gets people into trouble and 99% of the Explorer drivers out there don't need LO range.

 

[LuLu71730]

Thanks for your help!

purely electrical.............hmmmm

I'll do it in the morning, but I did try that and it was still "stuck" in low, I can't remember exactly what speeds it shifted out at but I'll do it again. Thanks again!

If I ever get it out of 4L it won't be going back in it, LOL!

 

[LuLu71730]

Is there something I can unplug to get it to disengage? If I run diagnostic scan with a obd II scanner will this show anything?

 

[LuLu71730]

What are the hall sensors and where are they located?

 

[IZwack]

No there is nothing you can disconnect -- 4LO engagement is mechanical.

The hall sensors are right near the output flanges (both front and rear output flanges). They are solid state devices (no moving parts) that detect rotation based on a set of teeth (the "tone ring") passing by a magnet which induces electrons to fluctuate in the sensor.

 

[LuLu71730]

This is going to sound odd but it has worked a few times to some users on here -- park the vehicle, rotate the transfer case switch on the dashboard to the AUTO position, and disconnect the battery for about 10 mins. Then reconnect it and take the vehicle for a spin and see if the transfer case is still in 4LO -- if its not, the RPMs should be a lot lower than when it was stuck in 4LO.

I did this again this morning and nothing, its still the same....... any more suggestions?

 

[IZwack]

Well then at this point, I would try shifting the transfer case back into Auto mode manually :

1) Park the vehicle on a level surface
2) Ensure that the knob at the dash is turned to AUTO
3) Disconnect the battery
4) Place a brick in front and beihnd one of the tires -- space them about 2" from the tire so your vehicle can move a few inches
5) Shift the transmission into Neutral
6) Unbolt the shift motor from the transfer case but leave it plugged in electrically (zip tie it to something so its not just hanging).
7) Try to rotate the shift rod so that it points to the AUTO position with a pair of pliers -- you probably need someone to slowly rock the vehicle back/forth an inch or so to get the transfer case to shift. Don't put lateral (side-to-side) force on the shift rod or else its pin at the other end may break off -- keep it centered as you rotate.
8) Take a note of where the shift motor is pointing (mark it with a marker).
9) Reconnect the battery, put the key in (in the ON position but dont crank the engine), and the shift motor should rotate back to its Auto mode (your mark should have moved).
10) Bolt the shift motor back onto the shift motor.
11) Never shift the vehicle into 4LO again

 

[LuLu71730]

7) Try to rotate the shift rod so that it points to the AUTO position with a pair of pliers -- you probably need someone to slowly rock the vehicle back/forth an inch or so to get the transfer case to shift. Don't put lateral (side-to-side) force on the shift rod or else its pin at the other end may break off -- keep it centered as you rotate.

we have tried this but can not get the shift rod to stay pointed toward auto, it always springs back to low.

 

[IZwack]

we have tried this but can not get the shift rod to stay pointed toward auto, it always springs back to low.

Because the gears in the transfer case arent aligned -- you have to push the vehicle an inch or so to get them to align. Either that or there was pressure on the gears (maybe the transmission wasnt in Neutral, the vehicle was parked on a slight incline, etc..).

The pic below are of two shift rail/rod .. one has a broken pin (dont pay attention to that). You can see the clock spring on the left of the rails/rods which is giving you that spring back force

These are a few shots of the shifting mechamism (notice that 4HI and AUTO are the same position):

The pic below shows two "positions" -- 4HI/AUTO and Neutral. 4LO is towards the back of the helical ramp. Notice that there is a Neutral flat spot -- this exists but you can not get to this with the switch on the dash. However, the transfer case needs this Neutral area to switch from engaging one set of gears to another.

This is the gear (with its accompanying shift "fork") you are trying to align with another gear. The gear and fork must move forward (relative to the front of the vehicle) to engage the "AUTO" mode of the transfer case. In the pics above, the transfer case is already in "AUTO" mode (as in the fork and gear are all the way down since the transfer case's front is facing the ground).

 

[LuLu71730]

WOW, Thanks for the pics! Let me study this for a while and I'll be back.

one more thing, when we hear the shift motor "running/turning" is it springing back too because of the pressure?

 

[LuLu71730]

ok we got the shift rod turned toward 4H, put everything back together and drove it...... its still the same.

 

[IZwack]

Remove the shift motor again, if the shift rail/rod is pointing back at 4LO, then the problem is electrical. If its still pointing at 4H, then the problem is mechanical and the transfer case either needs to be replaced, or opened up.

 

[LuLu71730]

Is it possible to take the gears or something out of the transfer case and make it shift right?