Author Topic: np203 shift problems 4x4 2x4?????  (Read 18451 times)

Offline sander

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np203 shift problems 4x4 2x4?????
« on: January 05, 2010, 12:12:13 PM »
hello
i am sander from holland.
and i have a strange problem.
i have a np203 with warn hubs in the front axle ,
the problem is i cant get it in 4x4.
it is 2x4 constant doesnt matter in witch position the lever is, or the hubs.
the front axle turns verry light it seems there is something missing in the transfer case?????
everything looks ok and it all works fine
exept the 4x4 part
i am sorry my writing is bad  :'(
hope you can read and understand it
greets sander

Offline Captkaos

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Re: np203 shift problems 4x4 2x4?????
« Reply #1 on: January 05, 2010, 12:35:50 PM »
A NP203 is fulltime 4x4.  What is your shifter pattern?  L-Loc, L, N, H, Hi-Loc?
Does it have locking hubs?

Offline 4x4orbust

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Re: np203 shift problems 4x4 2x4?????
« Reply #2 on: January 05, 2010, 12:37:28 PM »
i can understand just fine.    welcome to the site!    

a np203 is a full time 4x4 transfer case, which means there is no selection for 4x2.  
read this thread to confirm you have a np203:
http://forum.73-87chevytrucks.com/smforum/index.php?topic=4177.0

check to make sure your front driveshaft is turning when it is in 4x4,  also double check the hubs, they  may not be engaging the driveshaft, thus causing your condition.
1982 chevy K-10 SWB, 355 th350/np208. 2.5"lift, 33" swampers, headers/duals,  current project

Offline sander

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Re: np203 shift problems 4x4 2x4?????
« Reply #3 on: January 05, 2010, 02:47:49 PM »
hello
thanks for the quick reply
it has warn locking hubs
if i turn the hubs to lock the drive shaft can not rotate by hand  so they lock the diff i think
if i than drive whith the lever in 4hi or 4l or lo lock and high lock only the rear wheels are ''turning''  ???(dont no the word in english)
if i unlock the hubs i can turn the front drive shaft by hand doesnt matter in wich gear it is
but i can still drive (rear wheels)
thanks sander

Offline sander

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Re: np203 shift problems 4x4 2x4?????
« Reply #4 on: January 05, 2010, 02:54:31 PM »
4x4orburst
i have read that thread only they have the problem it stays 4x4 and my problem is it doesnt get in to4x4 but stays 2x4
it is just the opposite :) :)

Offline 4x4orbust

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Re: np203 shift problems 4x4 2x4?????
« Reply #5 on: January 05, 2010, 04:12:41 PM »
seems like something went wrong in the conversion from full time transfer to part time transfer case.   did you do the conversion yourself?   i do not know much  about the np203, sorry i can't be of much more help, but there are others here who are much more knowledgeable than me!
1982 chevy K-10 SWB, 355 th350/np208. 2.5"lift, 33" swampers, headers/duals,  current project

Offline VileZambonie

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Re: np203 shift problems 4x4 2x4?????
« Reply #6 on: January 05, 2010, 04:15:46 PM »
If you lock the hubs you are locking essentially the front wheels to the front axles. So when they are locked the front driveshaft will not be able to turn unless the vehicle is moving. From what I understand you are saying this is what happens. So when you select 4WD did you verify the linkage is working correctly?
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Offline sander

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Re: np203 shift problems 4x4 2x4?????
« Reply #7 on: January 06, 2010, 03:07:41 AM »
if i lock the hubs i can not turn the front drive axles so that is ok when i then drive in 4hi or lock only the rear wheels are the ones that is power oneso it is still rear wheel drive the front axle is not powered
the linkage is working fine
i didnt do the conversion myself
it seems something in transfer case is wrong or missing
i just dont no what >:(

Offline Irish_Alley

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Re: np203 shift problems 4x4 2x4?????
« Reply #8 on: January 06, 2010, 03:51:42 AM »
I'm think something in the t case is broke, would a broken chain cause this problem?
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Offline joesgarage71

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Re: np203 shift problems 4x4 2x4?????
« Reply #9 on: January 06, 2010, 11:30:42 AM »
I think there would be no movement if the chain was broke
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Offline 4x4orbust

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Re: np203 shift problems 4x4 2x4?????
« Reply #10 on: January 06, 2010, 11:59:05 AM »
have you tried unlocking the hubs, then putting the transfer case in each of it's positions, and go under the truck and try to turn the front driveshaft? 
1982 chevy K-10 SWB, 355 th350/np208. 2.5"lift, 33" swampers, headers/duals,  current project

Offline sander

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Re: np203 shift problems 4x4 2x4?????
« Reply #11 on: January 06, 2010, 03:09:28 PM »
hello
yes tried that already.
can turn the driveshaft by hand if i unlocked the hubs.
..strange problem isn't it
i think there is something missing in the transfer case what else can it be

Offline Captkaos

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Re: np203 shift problems 4x4 2x4?????
« Reply #12 on: January 06, 2010, 05:21:39 PM »
Maybe the chain is broke.  Locking the hubs lock it to the pinion so that is why it won't turn.  The actaul part that locks the front and rear together is the diff in the back of the case.

Offline VileZambonie

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Re: np203 shift problems 4x4 2x4?????
« Reply #13 on: January 06, 2010, 09:07:53 PM »
I'm willing to bet it's a linkage problem or the actual shaft is not moving.
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Offline sander

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Re: np203 shift problems 4x4 2x4?????
« Reply #14 on: January 11, 2010, 01:17:03 PM »
hey
if i turn the front drive shaft the chain is turning.
if i turn the rear drive shaft the chain isnt'.
it seems like there is a problem inside the case,  can i ajust the shaft.
the linkage is working ok