NP246 is it possible to reassemble it wrong? Problem solved!!!

BC K1500

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The quick rundown;
I pulled the transfer case as the bearings were shot. I got the rebuild kit and went to work.

I put the TC in first and tried to put the encoder on after as not to rush damaging it while putting it in, that's when the trouble started. The notch on the TC did not align whit the motor.
After racking my brain I think might left the car in 4wd when driving it up the ramp.

After countless hours of trying to find a solution I found a post that explained how to activate the clutch so the gear can turn on the actuator and align whit the spline.

I bolted it up, turned the ignition on and shifted to neutral cycling trough different modes.
2H ok,
2Autook,
4HI makes some effort but it stays in, 4Low just flashing and doesn't do anything.

Then I turned the car on, did the same thing whit same results but when I attempted to put in 4lo it just made a bunch of loud kicking noises and didn't work.

I haven't driven it yet.

Now my question is, is it possible to assemble the shifter ring the wrong way or put the little tab on the clutch assembly not in the right position (between the fork) and still being able to assemble the case?

What is the most likely problem?
The encoder on wrong position or something not put back together in the case?

It would be a pita to pull it out again but I'll do it if I have to, I have very limited time to figure out the problem as my trip coming up very soon.

Also some posts suggested to pull the encoder apart and align the gears manually, that didn't work as that SOB would not come apart, it is the old style whit the flat notches on the shaft.

Any help would be appreciated.

1998 GMC K1500 Suburban.
 
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DonYukon

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So Its been a few years and this is minding that parts havent changed or been modified.

Take the encoder motor off and with it still plugged-in select 2wd. make sure that the Transfer case is also in 2wd. I've been told while not likely it is possible to replace a encoder motor in the wrong selection series. I personally cant think of how this can be done as the motor is keyed to the Case and it should be pretty obvious if the shaft doesn't line up but again this is what ive heard. Are you getting a SVS 4wd light or DTCs?

Also make sure your other connections are plugged in . remember the pigtail everyone forgets that's towards the top of the case.
 

BC K1500

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So Its been a few years and this is minding that parts havent changed or been modified.

Take the encoder motor off and with it still plugged-in select 2wd. make sure that the Transfer case is also in 2wd. I've been told while not likely it is possible to replace a encoder motor in the wrong selection series. I personally cant think of how this can be done as the motor is keyed to the Case and it should be pretty obvious if the shaft doesn't line up but again this is what ive heard. Are you getting a SVS 4wd light or DTCs?

Also make sure your other connections are plugged in . remember the pigtail everyone forgets that's towards the top of the case.
I did try that as well. the 2wd does not align whit the neutral position on the shaft.
I don't have any warning lights beside the blinking of the button.
All connectors are plugged in.

There is a short video, if you turn up the volume you can hear the clanking sounds. it is actually really loud.
xc_hide_links_from_guests_guests_error_hide_media
 

DonYukon

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well that encoder motor is working or at least trying thats for sure. question with the encoder motor out can you get the truck to actually get the inside of the case to hold 4lo or does it pop out? from the sounds of it Im not sure its holding the gear. also have you made sure the encoder motor is working properly?
 

BC K1500

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The encoder was working before pulling it. It is also moving when off the case and connected to wires and pressing the buttons .


I can move the selector shaft whit a wrench when the encoder is off in three position.
Middle is neutral I assume, up and down.
Just like this;
https://i1115.photobucket.com/albums/k549/oldyukon/encodermotorshaftselection.jpg

I drove it to work this morning and I think it is in 4hi as when making a very slow tight turn out of the parking spot the front wheel were slipping.

I found this solution that worked for someone on another board, the guy had the same issues whit the same encoder as I have;

- Raise the rear end and peg the front tires.
- Disconnect the battery to clear the TCC.
- Reconnect the force motor. letting it hang from the t/case.
- Turn on the vehicle and select the correct range, with the tranny in neutral.
- If the force motor lines up, turn of the vehicle, bolt it up.
- Turn on the vehicle again and leave the transmission in neutral.
- select the various settings on the t/case.

Does this sound correct?
Does this make sense to try?
What would be the point of raising the rear wheels of the ground?

Thanks.

Sorry for the formating, I'm writing this ony cell.
 

BC K1500

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UPDATE!!!

Ok, I figured out the problem. It was obviously my mistake, but I am not ashamed to post it as it might help someone.:cool:


So...
I ended up taking the TC out as the plroblem was obviously not in the ecncoder motor.

My 1st suspicion was that I might not put the plate that pushes the clutch fork in, somehow in the wrong position. Upon having a second look that would have been impossible.

2nd possibility I tought, I might not put that little tab on thr clutch braring between the fork as it should be, but that wasn't the case at all.

After wrecking my brain and checking everything possible the only option left is that something was wrong in tha clutch pack.
Countless videos later and beeing fairly certain I messed up by opening the clutch pack ( which everyone say shouldn't do) to replace the two bearings. It seemed like that a very expensive tool is needed to set the clutch pack properly. Thinking about this overnight I came to the conlusion that it would be practically impossible just by to take an old clutch pack apart to make it so thick that it would cause a problem.

So I dissasembled the clutch pack again just to realize that I put the clutch backing plate in the clutch housing back the wrong way, hence making it much thicker and therefore the encoder couldn't lift the fork up enough to put it in the right position. I don't know how I managed to do that because I was very carefully to assemble it the way it was.
Well... mistakes happen. All we can do is learn from them.:rolleyes:

I put it back togheter bolted it up and it works as it should.

Thanks for everyone trying to help. :cheers:
 
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