Transfer Case will not disengage

[tmlub]

Good evening folks. I am trying to help my future daughter-in-law fix her explorer. '98 V6 127000 miles. The transfer case seems to be locked in one of the 4WD slots. Her dad removed the front drive shaft but it still seems to be in 4WD. I disconnected the wiring harness underneath and drove it but nothing changed. I'm not very familiar with 4x's so I don't know where to start. I have read many threads here and none seem to be exactly what my problem is. Thanks in advance and I apologise for the length of this post.

 

[IZwack]

How do you know its in 4wd (need symptoms and behaviors) ?
Is the drivetrain binding and are the wheels chirping/sliding going around tight turns (almost feels like the engine is going to die)?

If the front driveshaft has been removed, then at that point, it doesn't matter whether or not the transfer case is in 4wd or not, the vehicle is mechanically incapable of 4wd.

 

[tmlub]

It just feels like it is stuck in 4low. It drives the same as a Jeep I used to have in 4low. I can feel the transmission shifting thru all of the gears but I'm showing 2000RPM @ 30MPH in 3rd. When I get to about 10-15MPH the O/D off light starts flashing. I also had some one start it and move it slowly while I laid beside it and the transfer case coupling for the front drive shaft was turning.

 

[tmlub]

As I re-read my last post the concept of Auto/4High/4Low finally sank in. Now I'm more confused than I thought I was.

 

[IZwack]

Okay if its stuck in 4LO, try disconnecting the battery for like 5 mins and reconnecting it -- we're not sure why it works, it just does. It that doesnt work, then you are probably going to need to remove the shift motor and turn the shift rail rod thing by hand so it points back to "4H" as opposed to "4L" (which is where it should be pointing). To do so, block off the wheels on flat ground so the vehicle doesnt roll, put the key in the iginition but dont crank the engine, then move the transmission to Neutral and then remove the shift motor and rotate the shift rail.

This sub-forum has quite a bit of good "Sticky" threads on 4wd engagement and transfer case operation. For example: http://www.explorerforum.com/forums/showthread.php?t=203441

 

[tmlub]

Thanks Izwack. I will try that tomorrow afternoon and let you know. I appreciate your help.

 

[tmlub]

I tried disconnecting the battery and it didn't work. I will try to change it manually as soon as I get the chance. Unless you think it could be one of the relays. But I did disconnect the whole wire harness and it didn't change anything either. Thanks again.

 

[tmlub]

I removed the motor this afternoon and tried to manually turn the shaft. It was marked on the TC (4L N 4H) with arrows pointing from "N" to the left and right toward the other positions. It is stuck in the 4H position. I turned it to "N" but it will not stay. It seems to be spring loaded. I turned it as far as I could past "N" toward the 4L position but it would not change. It is lookng like it will have to go to the shop. Thanks for your help this far. At least I did learn something.

 

[IZwack]

The goal is to have it pointing into the 4H position -- not 4L.

Are you 100% positive the vehicle is driving in LO gear? If you do, drop the transfer case and rotate the rear output flange and watch the front input shaft. If the two rotate at the rate, then the transfer case is fine. If the input shaft rotates about 2.5 times faster than you rotating the output flange, then the transfer case needs to be opened.

On the other hand, the problem might be that the torque converter isn't locking up -- could be indicated by the flashing O/D light. This would explain the high RPMs. I'd get the vehicle scanned for the error code.

 

[tmlub]

I am not 100% positive that it is in LO. The pointer on the shaft is pointing to the 4H position. I will have to put it in the shop to get the transfer case dropped. I don't have a place to do it myself. I did scan it with a obdII scan tool and there are no codes. Thanks again.

 

[gijoecam]

The hard shifting could be caused by a trans problem, as evidence by the blonking OD light. That means that a fault has been detected with the transmission, and a code has been stored. Any OBD-II reader should be able to find it...

You also mentioned 2000 rpms = 15 mph in 3rd gear... If it was truly shifting through all the 'gears' (and I use that term loosely), there would be five of them, not three. Again, the fact that you're only experiencing three gears makes me thing transmission, not transfer case.

Now, when you attempted to manually put it in low range, was the vehicle in park with slight rearward pressure on the drivetrain, or was it in neutral with the wheels chocked? It should have been in neutral with the wheels chocked... Otherwise the pressure from the vehicle resting against the park pawl in the transmission would prevent it from releasing the gears as the pressure of the gears in that direction tends to force them together.

The blinking OD light leads me to believe it's a trans issue, not a t-case issue. Also, the fact that the transfer case is in high range leads me to believe there's no problem there.

-Joe

 

[tmlub]

Thanks Joe, I did have it in neutral with the motor running when I tried to manually change the transfer case. Based on what IZwack has told me and now with your help the transmission is starting to sound more like the culprit. I will get it to a transmission shop as soon as I can. Thanks again to both of you for all of your help.