Np203 Transfer case problem

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huntemcd79k10

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I have a question on a np203 transfer case. What is the shifting pattern first of all. Ive read that the Low is up towards the front but on mine that is high. Right now i have the lever all the way up which that should be loc right? My driveshaft on the front isnt spinning at all. and with it in loc and the hubs on free i can spin the driveshaft by hand. Any help will be appreciated.
 

75gmck25

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The shift linkage on the NP203 can get out of adjustment, so first adjust the linkage. It make take some work to get it lined up.

If you have locking hubs then you must have a conversion kit installed in your NP203. Lockouts were never used with an unconverted NP203.

Once you think you have the shiter adjusted:
Move the shifter down to the middle position and make sure you find neutral. In this position you can put the truck in drive and it will not move.
- Then shift it down toward the seat one position, which should be High (2WD high on a converted case). Drive it in this position at a steady speed of about 30 mph and listen to the engine.
- Now move the shifter back up and find neutral. From there shift it one position toward the dash to Low (2WD low on a converted case). Drive at the same speed and it should be obvious that the engine is revving much higher.



Bruce
 

huntemcd79k10

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The shift linkage on the NP203 can get out of adjustment, so first adjust the linkage. It make take some work to get it lined up.

If you have locking hubs then you must have a conversion kit installed in your NP203. Lockouts were never used with an unconverted NP203.

Once you think you have the shiter adjusted:
Move the shifter down to the middle position and make sure you find neutral. In this position you can put the truck in drive and it will not move.
- Then shift it down toward the seat one position, which should be High (2WD high on a converted case). Drive it in this position at a steady speed of about 30 mph and listen to the engine.
- Now move the shifter back up and find neutral. From there shift it one position toward the dash to Low (2WD low on a converted case). Drive at the same speed and it should be obvious that the engine is revving much higher.



Bruce

On mine high is toward a the front of the truck. I put it all the way up and brought it back one more and it was still high and then one more was neutral. All the way back is low. And I have lockouts with the conversion kit too. I think it may be the chain in the t case. Thanks for your help.
 

Craig 85

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Starting at the dash going towards the seat. Low lock, Low, Nuetral, High, High lock. My '79 truck has a P/T kit with locking hubs. With that, High becomes 2wd High (normal driving) and Low becomes a 2wd Low.
 

huntemcd79k10

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Starting at the dash going towards the seat. Low lock, Low, Nuetral, High, High lock. My '79 truck has a P/T kit with locking hubs. With that, High becomes 2wd High (normal driving) and Low becomes a 2wd Low.

Huh. Well mine is the opposite.
 

Big red square

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Starting at the dash going towards the seat. Low lock, Low, Nuetral, High, High lock. My '79 truck has a P/T kit with locking hubs. With that, High becomes 2wd High (normal driving) and Low becomes a 2wd Low.
What's the point of 2 low?
 

77 K20

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I use it when driving up to old fire lookouts in the summer (or any very steep climb). The roads are typically very rough and steep. 2wd was all that was needed and the speeds typically were 25 mph and under. Using 2wd low reduced lugging the engine climbing then when descending there were multiple gear options for slowing without riding the brakes for miles.
Or you can do a burnout with a old tired engine... :burnout:

full

full


Tires aired down to 12 psi and a rear locker made it possible in 2wd. Found this video of a motorcycle going up it:

xc_hide_links_from_guests_guests_error_hide_media
 
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77 K20

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I even confuse myself if it has been a few months since I've driven it. I finally ordered shift knobs that have laser engravings showing what they do. Hopefully they are here tomorrow.

full
 

TJ1978

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For the twin stick np203 which I have and is now not available from ORD any longer or temporarily
 

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SquareRoot

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I even confuse myself if it has been a few months since I've driven it. I finally ordered shift knobs that have laser engravings showing what they do. Hopefully they are here tomorrow.

full
Sweet! I love shifting it. The triangulated bracket I made for it is dead solid and the shifter throw is only about and inch in either direction. I was driving it around the house in front wheel drive while I was waiting on my rear shaft.
 

Big red square

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I use it when driving up to old fire lookouts in the summer (or any very steep climb). The roads are typically very rough and steep. 2wd was all that was needed and the speeds typically were 25 mph and under. Using 2wd low reduced lugging the engine climbing then when descending there were multiple gear options for slowing without riding the brakes for miles.
Or you can do a burnout with a old tired engine... :burnout:

full

full


Tires aired down to 12 psi and a rear locker made it possible in 2wd. Found this video of a motorcycle going up it:

xc_hide_links_from_guests_guests_error_hide_media
Burnout enough said.
Thanks lol.
 

bucket

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For the twin stick np203 which I have and is now not available from ORD any longer or temporarily

Yeah, I hope they bring that kit back. It will be annoying to build my own setup, knowing that a kit used to exist and it was affordable too.
 

TJ1978

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Yeah, I hope they bring that kit back. It will be annoying to build my own setup, knowing that a kit used to exist and it was affordable too.
maybe theyre just be phasing all things 203 out unless you go doubler. But they have the 203 rebuild kit, so who knows.

I have a 205 waiting to go in, but I honestly don't want to hassle with the swap until my 203 dies. Hahahahah. Putting that 203 in solo was not fun at all. I imagine the 205 is slightly easier but still a pain.
 

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