4x4 shift problems

[vwtinman]

I shift into 4H or 4L and the light comes on. However, it is not in 4WD. Is the shifting motor on the transfer case working if the light comes on? Do you think it is in my hubs (which aren't manual) or the shifting motor, or?

 

[K.S.MADMAN]

There no hub on 95 & newer ex. show i would be looking at the transfer case motor . try moving the switch from 2hi too 4hi a few times and see if it's go in. you may need to clean the wire plug on the transfer case motor . http://www.therangerstation.com/tech_library/TCaseshiftmotor.htm

 

[vwtinman]

I'll be checking out that motor today. I'll let you know, Thanks!

 

[farmtruckman]

Same Problem with my 95

I had the same problem earlier this week with my 95. Even though you shift, no movement, just a lot of noise of gears not quite engaging. You might try taking a hammer and gently tapping the motor portion. It freed up the motor on mine and allowed me to get home. I know that sooner or later, I am going to have to replace it, but for now, because of winter, I am not planning on shifting out of 4wd auto for a few more months. Great post somewhere in the forum about rebuilding the motor. Good Luck.

 

[gijoecam]

The motor has nothing to do with the transfer case lockup on a 2nd gen Explorer. (with the exception of the Sport Trac and the '01-03 Sport) The problem on a 95 or 96 can generally be traced to issues with the center axle disconnect, or the electro-vacuum system that controls it. First, we need to confirm that the transfer case is locking.

In 2wd, verify that the front driveshaft turns freely.
Jack the front wheels off the ground. Lock it into 4low and try to turn the front driveshaft. If it turns, you have a t-case issue. If it doesn't turn, we need to check the front axle.
Check the front axle: Again, locked in 4low, spin one front wheel. If the other front wheel does not spin the opposite direction, the front axle's center axle disconnect is not locking in. We can troubleshoot that further if necessary.

Check it out and let us know what you find.

 

[BogFather]

4x4 Not Working

Am having the same problem as far as i can tell. i thought at first it was the transfer case motor or Actuator. so i went and had the motor installed and guess what NO fix still no 4x4. . any suggestions would deffinately be useful as winter is here and i wanna get back out in the woods

 

[gijoecam]

Am having the same problem as far as i can tell. i thought at first it was the transfer case motor or Actuator. so i went and had the motor installed and guess what NO fix still no 4x4. . any suggestions would deffinately be useful as winter is here and i wanna get back out in the woods

A 2000 won't have the same problem as a 95 or 96. The 95/96 were the only ones that used the center axle disconnect. For 97-01, jack up the front end, lock it in 4high with the key on, engine idling, and see if the front driveshaft can turn.

-Joe

 

[oldwrench61]

have like 4x4 issue as described above - tried gijoe's advise

So I have '96 Explorer which appears to have like symptoms as tinman and farmtruckman describe. In short, all indictors are that 4x4 system is ok (lights functioning properly, shifting into Lo-range, etc). Problem is the front wheels are NOT being powered.

Thus far I believe I've elminated the center axle disconnect and have just replaced the t-case shift motor to no avail.

So I pursued gijoe's troubleshooting recommedation and came up with the following:
- in 2wd the drive shaft turns feely; the front wheels turn freely
- in 4H/Auto I can turn the driveshaft (albeit it is considerably harder to turn); the front wheels turn in opposite directions
- 4L...same results as 4H
- spinning front wheel results in other one spinning opposite direction

should we assume the center axle disconnect is locking up?

perhaps issue is in t-case...sensors or lock up mechanism (if there is such a thing)?

Any further thoughts, troubleshooting suggestions, or questions would be appreciated.

Thanks gijoe for your contribution thus far.

 

[gijoecam]

Y'know, to be honest, I've never actually tried my troubleshooting to ensure it's accurate... It's possible that, since the vehicle is not moving, activating the t-case at near-minimum-duty-cycle, one might, in fact, be able to spin the driveshaft. I honestly never thought of that until right now... I'd go jack mine up and try it right now, but the upper half of the motor's torn apart. As soon as I get it back together, I'll check mine out to confirm.

Now, that being said, If we assume, for the moment, that my assumption in the troubleshooting is correct (i.e. the t-case should lock even when standing still) if the t-case is not locking, but it appears the CAD is (since the wheels spin opposite directions, I would say you have an issue with the transfer case not locking like it should. I can see it not locking solid in 4auto, but I would have thought 4low would hold it... Maybe, at minimum duty cycle in either case, the system will still allow you to manually turn them? :dunno

Help!! Can someone try it out and let us know? Jack the front end up, lock it in 4low, and see if the front driveshaft can be turned by hand with the trans in park.

-Joe

 

[oldwrench61]

thanks gijoe

Thanks for your reply. At this point I'm gonna do some research on the t-case, wheel speed sensors, etc. to better understand the functionality.

Thought...is it your understanding that the dynamic lock up/unlock of the front wheels (based on rear wheel spin) occurs in the t-case or the front axle CAD?

 

[gijoecam]

Thanks for your reply. At this point I'm gonna do some research on the t-case, wheel speed sensors, etc. to better understand the functionality.

Thought...is it your understanding that the dynamic lock up/unlock of the front wheels (based on rear wheel spin) occurs in the t-case or the front axle CAD?

T-case. The factory service manual makes it pretty clear. I've quoted it on here a bunch of times, but don't have the program up and running on my computer at the moment...

-Joe

 

[farmtruckman]

My problem is definately the shift motor. Since tapping it and having it go into 4WD Auto, have had no problems. Starting planning on replacing the motor this afternoon and began shifting back and forth between 2WD and 4WD Auto and it failed again. Transfer case stuck somewhere in between and when you slip it into gear, sounds like gears trying to connect but not close enough. Tapping on the motor freed it up again. Repeated it once to be sure so now I am in the process of swapping out shift motor.

Be wary if you try this, the intructions that came with the motor I bought are misleading. It is not a unplug/plug and go, you have to swap pins from the speed sensors which are a pain in the rear. Quit on it for tonight and will tackle in the AM to finish, 5 more pins to swap out.

 

[Ray Lobato]

My problem is definately the shift motor. Since tapping it and having it go into 4WD Auto, have had no problems. Starting planning on replacing the motor this afternoon and began shifting back and forth between 2WD and 4WD Auto and it failed again. Transfer case stuck somewhere in between and when you slip it into gear, sounds like gears trying to connect but not close enough. Tapping on the motor freed it up again. Repeated it once to be sure so now I am in the process of swapping out shift motor.

The shift motor only moves the transfer case from HI to LO. It does not engage the 4 wheel drive system. If you have a problem going from 4HI to 4LO, then you have a possible problem with the shift motor. If you can't engae 2wd to 4wd, it is a problem with the transfer case itself.
I can't elaborate on it right now, but will add to this later.

 

[oldwrench61]

Thanks Ray. Seems that all fingers are pointing to the t-case. Looking fwd to verifying and understanding the interworkings to determine if it's repairable, or the unit needs to be replaced.

Farmtruckman - yeah I hear ya wrt to installing the shift motor...went through the drill earlier today. Concerning porting the (7) sensor wires/pins from the old motor wire plug to the new, found this quite easy once I broke the code. Couple notes: if you've not done so, pull the red plastic piece out of the inside of old plug before attempting to dislodge pins; from the inside of the plug, i used a (ice)pick style test light to press the plastic lock tab (which holds the pin in) to the side, while simulanteously pressing the tip (of the ice pick) into the pin and pushing it out; once the pin is pushed down just a little to clear the lock tab, you can then just grab the wire and pull it right out; found the pins slid easily into the new plug; lastly i put the red plastic piece in the new plug.

 

[gijoecam]

My problem is definately the shift motor. Since tapping it and having it go into 4WD Auto, have had no problems. Starting planning on replacing the motor this afternoon and began shifting back and forth between 2WD and 4WD Auto and it failed again. Transfer case stuck somewhere in between and when you slip it into gear, sounds like gears trying to connect but not close enough. Tapping on the motor freed it up again. Repeated it once to be sure so now I am in the process of swapping out shift motor.

Be wary if you try this, the instructions that came with the motor I bought are misleading. It is not a unplug/plug and go, you have to swap pins from the speed sensors which are a pain in the rear. Quit on it for tonight and will tackle in the AM to finish, 5 more pins to swap out.

As Ray mentioned, the shift motor plays no part in transfer case lockup. The motor on a second-gen is solely responsible for engaging/disengaging the low range planetary gear set. If it won't go from 2wd to 4auto on a 95 or 96, the shift motor has nothing to do with it. Having it work after banging on the shift motor is mere coincidence.

 

[farmtruckman]

Finally finished the shift motor install. OldWrench61, I would like to meet you if only to see a man with 3 hands. Your tip using the test light "ice pick" pointed end was pure genius but holding one in one hand keeping the tab open, using another hand to push the pin in and using the third hand to hold the entire plug from moving around...wait, I only have two hands. Difficult but obviously doable but easier with your added ability. Seriously, thanks for the tip, it made the job much easier. My hydralic jack is low on oil so I could only get the X up so high so my working environment was limited.

As for Ray and GIJoeCam, Guys, I don't believe in coincidence. Maybe I was incorrect or inadequate when I explained the condition which led me to conclude that the shift motor was bad but it now works! There is more than enough snow and slush in front of my house to test every mode this morning, repeatedly. As far as the tapping on the motor, I did that four different times and each time it worked. I know how Einstein defined stupidity but in this case, it did work. Also, I am not smart enough to figure that one out by myself but read about tapping on the shift motor in this site by a guy that had a similar condition and was temporarily able to put it into one of the modes until he replaced the motor.

Thanks, all of you for your input. I definately have a better understanding of what makes these things tick and I owe that to each of you guys along with the entire site. Now, to move on to another problem that if I can't fix, I know that someone out there has already experienced it.

 

[Ray Lobato]

The shift motor only moves the transfer case from HI to LO. It does not engage the 4 wheel drive system. If you have a problem going from 4HI to 4LO, then you have a possible problem with the shift motor. If you can't engage 2wd to 4wd, it is a problem with the transfer case itself.
I can't elaborate on it right now, but will add to this later.

FOR 97-01 EXPLORERS

The engagement of the front drive line is done at the transfer case.
There is a solenoid that engages the clutch system, in the transfer case to engage the front drive line. A signal from the GEM goes to this solenoid. (Search for Brown Wire Mod)

What can happen to not go into 4WD.

1) No signal present to solenoid.

Check all connections coming from the GEM to the solenoid. It's either not coming from the GEM or bad/broken connection between GEM and solenoid.


2) Signal present but solenoid doesn't work

Bad solenoid. Replace solenoid.

3) Signal present, solenoid works, but still won't engage front drive line.

The clutch system in transfer case is bad. Repair or replace transfer case.

4) No signal coming from GEM.

I believe that there are only 2 things to cause the GEM to send a signal to go to the transfer case solenoid.

A) The ABS sensors go to the GEM and it monitors wheel slippage (Control Trac).
In Auto4WD the ABS system tells the GEM that your wheels are slipping and to engage the front drive line. It's either on of off, there is no in between.
B) The mode selector switch.
Moving the selector switch from Auto4WD to 4WD.
This sends a signal to the GEM telling it to engage the transfer case solenoid.

​

If you don't have a problem with either of these signals getting to the GEM, then you have a bad GEM.

That's the way I see it. If I'm wrong on any of this stuff, Please chime in and correct me.

Note that I purposely didn't mention anything about the 95-96.
They have some sort of coupling thing happening at the front differential, but I don't don't anything about how it works. (Search for Brown Wire Mod)

Hope this helps.

 

[Ray Lobato]

As for Ray and GIJoeCam, Guys, I don't believe in coincidence. Maybe I was incorrect or inadequate when I explained the condition which led me to conclude that the shift motor was bad but it now works! There is more than enough snow and slush in front of my house to test every mode this morning, repeatedly. As far as the tapping on the motor, I did that four different times and each time it worked. I know how Einstein defined stupidity but in this case, it did work. Also, I am not smart enough to figure that one out by myself but read about tapping on the shift motor in this site by a guy that had a similar condition and was temporarily able to put it into one of the modes until he replaced the motor.

I can understand why you would think that way, but let's go a little further.
The shift motor IS connected to the transfer case, correct?
Banging on the shift motor sends vibrations to the shift motor, BUT it also sends vibrations to the transfer case.
I do know that the clutch system, in the transfer case Don't always work. This is why I have an Atlas II in my truck now.
I too had problems with my truck not going into 4WD sometimes, and thought it was the shift motor, because someone said to bang on the shift motor it will make it work, AND IT DID!!!, but after looking at this for awhile, and getting information from people like Joe, I realized that it was the vibrations from the banging on the shift motor, that was causing the clutch plates to come together and engage the front drive line.

If you pull the shift motor off and look at the stub coming out of the transfer case, you will note that there are actually three positions written on the plate.
There is Hi, Lo, and in between the two is Neutral, which allows you to tow your truck without ruining the transmission. Ford used to charge 50 bucks to attach a switch to the GEM that would allow the shift motor to go to the neutral position. I don't believe that they do this anymore.
Getting back on track now.
Look at that stub and look at what it says.
When the shift motor moves, it will only do two things.
It will move the transfer case gears from HI to LO, and from LO to HI.
That's all it does. I don't include the secret neutral, because most people don't even know about it. That's why I say 2 things and not 3 things.

The motor moves the transfer case gear from HI to LO, LO to HI.
Now We have 4WD HI and 4WD LO, but what about 2WD?
Where does the transfer case go in 2WD?
That shift motor doesn't say 4WD HI or 4WD LO or even 2WD HI or 2WD LO.
It's just HI or LO, and in 2WD the transfer case is in HI, The same HI that you use in 4WD HI. If this is true, then there must be something else that makes the truck go into 4WD, and that's the clutch system IN the transfer case, that just so happens to have the shift motor connected to it so when you bang on the shift motor, you are also banging on the transfer case, and the vibrations will also be felt by the clutch system.
Hope this helps.

 

[farmtruckman]

Ray, I think a point is being missed here. Your explanation of the function of the switch is no doubt accurate. As I said in a previous post, I now have a deeper understanding of how the TC functions. I still stand on what happened in my situation. I thought that in the original post by VWTinman, the conditions I experienced may apply to his failure. My memory might be incorrect, but the original post that I saw which led me to the "tapping" procedure mentioned a shift motor failure, and mentioned something about the brushes failing, and the motor not engaging to turn the selector in the TC. I feel that is what was happening to my 95. After shifting between 2WD and 4WDAuto, (or reverse direction), I would get a whirring sound "as if the transmission was not engaging" (my words). I didn't think of crawling underneath and trying to isolate the sound but it might have been the motor itself coming apart internally. I plan to now dig through the trash and retrieve the old motor and disassemble it. I will let you know what my findings are.

You may be totally right on the condition of the TC. Your knowledge of the operation of the TC is way above mine. My 95 however, has only about 20 hours since it was new in 4WD Auto (wife's soccar mom car before my kid inherited and now reinherited by me), so I tend to think that with the proper lubrication it had and minimal use, the TC was still good. I have seen, though, magnets rot out with age and motors fail.

As I said, my initial description of the failure may be lacking and my interpretation of the initial post from VWTinMan might be wrong. However, I still feel that he should look at all possibilities. I paid $75 for a new shift motor on Ebay and it took a few hours of my time to replace. That is a cheap repair by my book, especially in comparison to the cost of a new/rebuilt TC. This morning, I have repeatedly been cycling the system through all of the funtions with no failure. Prior to the replacement, I had 100% failure of the system to select a mode.

I will follow on later, once I disassemble the motor. I have to drive the X to Seattle for a few days using 4WD Auto in the Cascades, so if it fails, I will gladly notify you so I can eat the appropriate crow.

 

[gijoecam]

We're not trying to gang up on you and we won't make you eat crow if it turns out the problem is not fixed... I honestly hope you don't think that's what we're going for here. I apologize on behalf of myself and Ray if that's the impression you're getting... I'm sure it's not the impression we're trying to make.

The banging on the shift motor trick works and works well on those vehicles that actually use the shift motor to engage and disengage the 4 wheel drive. The point Ray and I are trying to make is that your truck is not one of them. Yes, banging on the motor may have worked, but hitting a pot-hole might have as well. It's quite possible that the original problem was simply a bad connection on the brown wire's terminal in that connector, or a corroded wire inside the insulation making intermittent contact. Now that you've opened up the connector for the re-pinning, you've disturbed those connectors/connections, and it may work for a little while, or it may work forever. Only time will tell.

But, it doesn't change the fact that the transfer case shift motor had absolutely nothing whatsoever to do with the problem of 4auto not engaging.

You wrote,

"My memory might be incorrect, but the original post that I saw which led me to the "tapping" procedure mentioned a shift motor failure, and mentioned something about the brushes failing, and the motor not engaging to turn the selector in the TC. I feel that is what was happening to my 95."

And that's where your logic is flawed. What you 'think' was happening to your truck is a physical impossibility. The shift motor does not turn to engage 4auto. Between 2wd and 4auto, the transfer case synchronizes the front and rear driveshaft speeds, then locks in the front axle's center-axle disconnect using an electro-pneumatic system to move an actuator on the passenger side axle shaft. That's it. The shift motor never moves.

You also wrote,

My 95 however, has only about 20 hours since it was new in 4WD Auto (wife's soccar mom car before my kid inherited and now reinherited by me), so I tend to think that with the proper lubrication it had and minimal use, the TC was still good. I have seen, though, magnets rot out with age and motors fail.

Again, your assumption is incorrect. Though the electromechanical ball-ramp assembly may not have been energized for most of its life (i.e. when in 2wd) the transfer case is in constant use at all times. Power from the transmission drives the transfer case input shaft which, in turn, drives the output shaft. The output drives the oil pump that feeds it all. Although the t-case was not locked, in all reality, due to the design of the case, the fluid shearing between the components of the t-case forces the front output to turn most of the time. It's not transmitting any power, so wear and tear is minimal, but it's not sitting there idle like a conventional part-time 4wd transfer case (e.g. the 13-54 from the 1st gens and Rangers).

Also, due to the design of the case and the gears, when the truck is coasting against the engine (i.e. downshifting or engine-braking) the helical cut on the planetary gears tries to force the low range gear set out of position. Ordinarily the shift fork and rail are able to hold it in place to prevent it from moving. However, over time, the shift rail bores wear, as do the fingers on the shift fork, and over time, the planetary gears are able to move. That results in the infamous 'buzz' or 'grind' from the transfer case on coasting with an eventual loss of reverse and, shortly thereafter, forward. We're seeing more and more of those symptoms around here as the early 2nd gens begin to get up there in age. It's not a flaw of the system, per-se, but it's certainly turning out to be its achilles heel.

Anyways, my point is that even without ever using the 4wd, the transfer case is still seeing a significant amount of wear and tear in everyday (even soccer-mom) driving. Please don't think it's bulletproof just because it's been seldom-used over its life.

Regards,
-Joe