4x4H Not disengaging

[tweets_5]

2002 EB 4x4 w/ 5.4

Truck is stuck in 4H, when i flip back to A4WD it stays in 4H, however it will go back and forth between 4H & 4L. My initial thought was transfer case shift motor, but would it still go to 4L if that was bad?

 

[toms89]

Pull fuse 104 in the engine bay. Should disable the clutch.

As far as I am aware the shift motor is used to switch between 4hi and 4low. There is an electronic clutch internal to the transfer case that engages / disengages 4wd.

 

[tweets_5]

Pull fuse 104 in the engine bay. Should disable the clutch.

As far as I am aware the shift motor is used to switch between 4hi and 4low. There is an electronic clutch internal to the transfer case that engages / disengages 4wd.

Pull it and drive it for a while and it should disengage? I tried pulling the other day and went around the block and didn't notice any change so I put it back in. I've also tried reverse and forward multiple times, tried pulling battery cable and then rolling down a hill to disengage, hadn't had any luck.

 

[bedrck46]

Problem
The Vehicle Does Not Shift Between A4WD and 4WD Modes Properly

Things to check

4WD mode switch.
Circuitry.
CJB Fuse 23 (10A).
A4WD clutch relay/circuit.
Contact plate sensors A, B, C and D circuits.
Transfer case shift motor/circuit.
Transfer case shift relays.
Transfer case mechanism.
GEM.

 

[FordandPolaris]

Pull fuse 104 in the engine bay. Should disable the clutch.

As far as I am aware the shift motor is used to switch between 4hi and 4low. There is an electronic clutch internal to the transfer case that engages / disengages 4wd.

I think this would only apply if it were already out of 4H and in A4WD. I believe 4H is a mechanically locked setup so the magnetic clutch is not used.

 

[bedrck46]

I think the key words were Between and Properly it appears that he can't get back to A4WD. I would think that wouldn't be proper between the two shift points also the information came directly from the service manual.

 

[FordandPolaris]

I think the key words were Between and Properly it appears that he can't get back to A4WD. I would think that wouldn't be proper between the two shift points also the information came directly from the service manual.

I was just pointing out fuse 104. I agree that the best way to test is what you posted previously.

 

[tweets_5]

Problem
The Vehicle Does Not Shift Between A4WD and 4WD Modes Properly

Things to check

4WD mode switch. Switch works i think, you can hear clicking when under truck
Circuitry. what exactly would i check?
CJB Fuse 23 (10A). checked, its good
A4WD clutch relay/circuit. would this be fuse 104?
Contact plate sensors A, B, C and D circuits. I'm lost
Transfer case shift motor/circuit. I'm lost
Transfer case shift relays. I'm lost
Transfer case mechanism. I'm lost
GEM.

Any other help anyone can give? I'm not mechanically challenged usually, just really unfamiliar with 4WD systems. Any help greatly appreciated, thanks

 

[bedrck46]

can you read and understand an elect print do you have a DVM
It is possible that if a open circuit is in the selector switch when in the a4wd position that it wont go into a4wd but if the circuit is good in 4h or 4l then it would be able to shift between those two Not saying that the switch is the problem but it should be checked if you can understand a elect print you would see what I am referring to I can send you a copy of the prints if it helps

 

[bedrck46]

print attached Look at the 4 WHEEL DRIVE MODE SWITCH you would need to measure the resistance between pin 2 and 3 while rotating the selector switch you should have a reading in every position but if you are in the A4WD position and have no reading then that part of the circuit is open and would not allow you to go into A4WD if you have a reading when in 4H and 4L that would allow you to be able to switch between 4H and 4L

 

[toms89]

I think this would only apply if it were already out of 4H and in A4WD. I believe 4H is a mechanically locked setup so the magnetic clutch is not used.

My reasoning is based off of what I see in the "exploded view" of the transfer case. To me it appears the shift motor is tied directly to the planetary which engages / disengages 4 low. There is an seperate electronic clutch that engages / disengages drive to the front driveshaft. I would assume that 4 hi just keeps the clutch mechanism engaged full time.

I have not disassembled or worked on the transfer case personally so I admit I could very well be wrong in my assumption.

Edit: You are correct sir.

I studied my shop manual a bit more carefully and it appears the shift motor controls two "shift forks". One engages / disengages the planetary. The other is for "lock up". The electronic magnetic clutch is described for use during A4wd mode. I believe it is actually using the same clutch pack but its either activated via the magnetic coil or physically via the shift fork controlled by the shift motor.

Since disconnecting fuse 104 did not disable 4wd that leads me to believe the shift fork is physically stuck in the "lock up" position as pulling the fuse should have disabled the magnetic clutch.

I would refer back to bedrck46's post #4 for possible causes.

 

[mindgame]

Have you tried changing the transfer case fluid?

 

[bheckel1]

I am going to jump on here too, since I have the exact same problem.

First I would like to thank those that have offered up information here and other threads. I have been on this problem for 3 weeks and have read quite a bit.

THANK YOU!

My current thinking is that the clutch in the transfer case is physically stuck

I have pulled 104 for test purposes and will be running without it till the snow flies. My 02' does not have any locks or engagement of any kind on the front axle, just an open diff. I changed a wheel bearing yesterday and can tell you for certain there is no lock in there. There are holes in the casting where the the vacuum and lever would be but there is no evidence it was ever there. I changed the fluid yesterday and this seemed to improve the situation.

I was looking at the exploded view on google pix and I could not tell if the clutch could be serviced in the vehicle????

I have a leash on a transfer case used I may pick up if the numbers are right. Then I plan to deploy old used car lot tech and dump in a pint of brake fluid and run it till it is loose, though I wont do this without a new case in hand cause it could eat more than corrosion.

any thoughts would be appriciated. I have use of a full service shop on weekends and 12 hrs a day (the 12 I am not already working in it and I need to sleep, I am not 20 any more.)

 

[FordandPolaris]

I am going to jump on here too, since I have the exact same problem.

First I would like to thank those that have offered up information here and other threads. I have been on this problem for 3 weeks and have read quite a bit.

THANK YOU!

My current thinking is that the clutch in the transfer case is physically stuck

I have pulled 104 for test purposes and will be running without it till the snow flies. My 02' does not have any locks or engagement of any kind on the front axle, just an open diff. I changed a wheel bearing yesterday and can tell you for certain there is no lock in there. There are holes in the casting where the the vacuum and lever would be but there is no evidence it was ever there. I changed the fluid yesterday and this seemed to improve the situation.

I was looking at the exploded view on google pix and I could not tell if the clutch could be serviced in the vehicle????

I have a leash on a transfer case used I may pick up if the numbers are right. Then I plan to deploy old used car lot tech and dump in a pint of brake fluid and run it till it is loose, though I wont do this without a new case in hand cause it could eat more than corrosion.

any thoughts would be appriciated. I have use of a full service shop on weekends and 12 hrs a day (the 12 I am not already working in it and I need to sleep, I am not 20 any more.)

And you have ruled out the shift motor? It is possible you had bad luck and it burned out while in 4H. The transfer case can't disengage without the shift motor.

 

[bheckel1]

I went into it with the assumption that it would be the shift motor since I have had to put one in every 4x4 I have ever owned. alas it is not. I have been driving without 104 for days and is still engaged.

There has been something warming up over the pit for days but I will get under it for a bit tomorrow night. I have a wheel bearing to do and a brake tho.

She rides nice today tho, it has been a wintery mix here for 16 hrs. Off to scouts now.

Thanks

 

[FordandPolaris]

I went into it with the assumption that it would be the shift motor since I have had to put one in every 4x4 I have ever owned. alas it is not. I have been driving without 104 for days and is still engaged.

There has been something warming up over the pit for days but I will get under it for a bit tomorrow night. I have a wheel bearing to do and a brake tho.

She rides nice today tho, it has been a wintery mix here for 16 hrs. Off to scouts now.

Thanks

All fuse 104 does is deactivate the magnetic clutch, which is not used it if it was set into 4H. The magnetic clutch is only used during A4WD as a way to send variable ratios of power to the front wheels. Sorry to beat a dead horse, but I assume you replaced the shift motor and this is how you know it is not the problem?

Enjoy scouts, I was in it for years and am an Eagle Scout. Well worth the time and effort!

 

[bheckel1]

Thanks.
I pulled and tested the shift motor first thing. There are markings telling what position the shifter is in once you remove the motor. it said 2 which is awd I guess. It has snowed a couple of times here and I have to plow so I have not gotten back to it. I did get my other wheel bearing and brake done last friday tho. The Pit has a truck with a bad exhaust manifold gasket over it till I get all the bolts out then I can get my truck over it and get to the bottom of it once and for all.

I am an assistant SM and will take over as SM in February. My son is working towards life now and should have it before summer camp next year. I am very active and will always let the truck slide for scouts. I do have to pull a trailer to camp in march tho.

 

[FordandPolaris]

Thanks.
I pulled and tested the shift motor first thing. There are markings telling what position the shifter is in once you remove the motor. it said 2 which is awd I guess. It has snowed a couple of times here and I have to plow so I have not gotten back to it. I did get my other wheel bearing and brake done last friday tho. The Pit has a truck with a bad exhaust manifold gasket over it till I get all the bolts out then I can get my truck over it and get to the bottom of it once and for all.

I am an assistant SM and will take over as SM in February. My son is working towards life now and should have it before summer camp next year. I am very active and will always let the truck slide for scouts. I do have to pull a trailer to camp in march tho.

Picked a good vehicle to tow in. While I was in the troop my blue truck was pretty much the troop tow vehicle back when it belonged to my folks. Do you guys go to Tomahawk then (based on being in Wisconsin)?

 

[bheckel1]

4x4 fixed

1100 dollars later with new transfer case 4x4 engages and disengages.

I believe the awd clutch got damaged. I did not take the t-case apart to verify that cause I wanted it out of the shop. the lessor hypothesis was that the little ear broke off the fork so that it would not come out of 4x4.

I could have fixed either of those for far less money but its more work, truck down for 5 days insted of one and would still have a t case with 165k. now I have one with 210miles (one tank of gas).

Camp is at The army base this month. It is not a polar bear. We did a polar bear in DEC.

We went to Tomahawk scout reserve 2 years ago for summer camp. The boys loved it. there was some grumbling about the food but we all had a lot of fun. Tomahawk is out of council, which we do every other year. Last year was gardener dam, In bay lakes council. This year is Thesomas which is nearish but out of council, it is one of the top rated summer camps in the country.

Thank you all for all of your help but sometimes you just gotta change big$$ parts.