73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => 4 Wheel Drives => Transfer Cases and Front Drivelines => Topic started by: sander on January 05, 2010, 12:12:13 PM
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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
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A NP203 is fulltime 4x4. What is your shifter pattern? L-Loc, L, N, H, Hi-Loc?
Does it have locking hubs?
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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.
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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
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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 :) :)
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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!
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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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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 >:(
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I'm think something in the t case is broke, would a broken chain cause this problem?
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I think there would be no movement if the chain was broke
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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?
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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
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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.
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I'm willing to bet it's a linkage problem or the actual shaft is not moving.
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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
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you mean adjust the driveshaft? i dont think there is any way to do that.
how can you tell the chain is turning when you spin the front drive shaft?
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hey .i unbolted the rear off the case. then you can see the chain. when i turn the front drive shaft you can see it rotate. making sense?
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An NP203 works by a differential like a rear traction unit. The front is always locked to a chain, so it will alway turn with the driveshaft. If the diff unit in the T-case is bad, you just took off the part that makes the transfercase work. You would have to have it in high lock (which locks the diff) and see if the front turns.
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if i turn the front drive shaft i can see the chain turn. if i turn the rear drive shaft it does not. makes no differents wicth position the lever is.
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An NP203 works by a differential like a rear traction unit. The front is always locked to a chain, so it will alway turn with the driveshaft. If the diff unit in the T-case is bad, you just took off the part that makes the transfercase work. You would have to have it in high lock (which locks the diff) and see if the front turns.
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i am trying too find out what the part is that is missing. i bought the car whit this conversion so i do not know what they did with it
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This should help identify what should be in it.
http://www.offroaders.com/tech/Diagrams/np203.htm