Transfercase problems - won't stay in Auto/Hi 4x4

[Autobaud]

Hi all ! I'm new to posting in the forum but have read quite a few helpful hints over the past years. My wife took the Explorer (97, XLT, 4.0) a few weeks ago on a trip by herself and while driving suddenly the car felt like it lost its transmission. she called me saying the trans just blew and she cant drive anymore. I told her to switch the Auto, hi and low 4x4 switch and she got the 4x4 low to engage and was able to drive to a repair/junkyard place. they suspected the transfer case motor and replaced it with a what they called to be a "functioning one" and the explorer was able to drive in "auto 4x4" for a couple hundred yards before it popped out again and only was able to move in low 4x4 again. I got a car trailer and brought the explorer home.

my question now : do i need to replace the transfer case so i can drive in auto or hi 4x4 again or is there a way to lock the transfer case in auto or high 4x4 (as i never need the low 4x4 ) without replacing the whole transfer case ? (since the transfer-case-motor doesn't seem to be the problem) .. any help or troubleshooting tips appreciated...
notes - when trying to drive in auto or high 4x4 it does engage until you start driving and then seems to "pop out" again giving me a slight gear grinding noise. the only way to move the car again is going into low 4x4 and it will drive just fine there...

thanks in advance for help

 

[imp]

Hi all ! I'm new to posting in the forum but have read quite a few helpful hints over the past years. My wife took the Explorer (97, XLT, 4.0) a few weeks ago on a trip by herself and while driving suddenly the car felt like it lost its transmission. she called me saying the trans just blew and she cant drive anymore. I told her to switch the Auto, hi and low 4x4 switch and she got the 4x4 low to engage and was able to drive to a repair/junkyard place. they suspected the transfer case motor and replaced it with a what they called to be a "functioning one" and the explorer was able to drive in "auto 4x4" for a couple hundred yards before it popped out again and only was able to move in low 4x4 again. I got a car trailer and brought the explorer home.

my question now : do i need to replace the transfer case so i can drive in auto or hi 4x4 again or is there a way to lock the transfer case in auto or high 4x4 (as i never need the low 4x4 ) without replacing the whole transfer case ? (since the transfer-case-motor doesn't seem to be the problem) .. any help or troubleshooting tips appreciated...
notes - when trying to drive in auto or high 4x4 it does engage until you start driving and then seems to "pop out" again giving me a slight gear grinding noise. the only way to move the car again is going into low 4x4 and it will drive just fine there...

thanks in advance for help

First, 1997, can't recall exactly: do you have a three-position switch on the dash marked "4X4 AUTO", "4X4 HIGH", and "4X4 LOW"?

If so, your symptoms seem to indicate that the transfer case is likely NOT at fault. All the driving effort not calling for 4X4 action simply proceeds straight through the TC to the rear wheels. Upon sensing wheel spin, an electronic clutch in the TC is engaged automatically to drive the front wheels. In 4X4 HIGH, the clutch is continuously engaged. The fact that 4X4 LOW seems to work normally, rules out the clutch as the likely culprit.

I'm thinking electrical problem, either in the relays which send power to the TC shift motor, or the switch on the dash. Having no '97 wiring diagrams is a big hindrance here. I suggest if you can locate the 2 relays, possibly via the owners manual (if you have it), or on-line searching, start the vehicle, make sure it is NOT in 4X4 LOW, switch to 4X4 AUTO, shut off engine, then remove both relays. Start up, and if it drives normally, it will be using rear wheels only, no matter what. Then, the problem becomes isolation of the cause: switch or one of the relays- most likely the 4X4 HIGH relay, if you can determine which is which. Hope this helps! imp

 

[Flash]

What imp said, but I don't know where the relays are so i would have unplugged the shift motor.

*imp. The switch is Auto - 4x4 H - 4x4 L

 

[Autobaud]

Thanks guys, i'll give the relay removal and/or disconnecting the tc motor a try this weekend. even though i think the guys that tried to fix it when the wife was stranded tried disconnecting the motor while in auto (i told them to try it, but not sure if they actually did) - i'll just give it a try here to be sure if that works or not.

imp - Flash was right the option on the switch - they are auto, hi and low

 

[imp]

What imp said, but I don't know where the relays are so i would have unplugged the shift motor.

*imp. The switch is Auto - 4x4 H - 4x4 L

Unplugging the shift motor is OK, but if the dashboard switch is faulty, that would mask the real problem.

The relays are in a box under the hood. imp

 

[drdoom]

The transfer case will need to be rebuilt. This is a common failure point. I have had it happen more than once.

 

[imp]

The transfer case will need to be rebuilt. This is a common failure point. I have had it happen more than once.

Can you tell us exactly what went haywire in the TC? His symptoms seemed kind of varied, hard to picture. Thanks. imp