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Old 10-01-2018, 04:19 PM   #1
Texasz71
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Np203 shifter

Once I figure out my transmission shifting issue, I want to start looking at my np203.

Itll shift to everything except high. I tried spraying degreaser and trying to scrub the crap out of it, along with a healthy coat of pb blaster. Still not staying in high. So I want to twin stick it with the ORD kit. Can this be done with the tcase in the truck?

Anyone have a video or a good tutorial? I've googled plenty but cant seem to find out exactly what I need.

Thanks in advance
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Old 10-01-2018, 07:33 PM   #2
sweetk30
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Re: Np203 shifter

203 twin stick in vehicle super easy . no major mods required .

205 is part tear down IF YOU want full twin stick mod function . but that twin stick kit can go in also in the truck .
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Old 10-01-2018, 07:48 PM   #3
Texasz71
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Re: Np203 shifter

Sweet. Thanks man

Anyone have a good tutorial or video?
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Old 10-02-2018, 08:27 AM   #4
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Re: Np203 shifter

YOU TUBE has all you need. twin sticking np205's and np203's Happy sticking!!!
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Old 10-02-2018, 08:41 PM   #5
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Re: Np203 shifter

I'd check the lever positions in 4 high then disconnect the shift levers. It may still pop out which indicates it isn't the shifter, or the shifter needs adjustment.

https://www.google.com/search?source...64.PhRjihXqMsI
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Old 10-02-2018, 09:00 PM   #6
Texasz71
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Re: Np203 shifter

Quote:
Originally Posted by franken View Post
I'd check the lever positions in 4 high then disconnect the shift levers. It may still pop out which indicates it isn't the shifter, or the shifter needs adjustment.

https://www.google.com/search?source...64.PhRjihXqMsI
That's my problem, when I put it in high, the truck acts like it's in neutral. Then when I shift it down one more click down (closer to the seat), I know it's in lock because the tires chirp on turns.

Hoping a twin stick and some good adjustment will fix this
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Old 10-07-2018, 09:25 AM   #7
Chevyrestorerman
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Re: Np203 shifter

How much adjustment is there on a np203 TC as far as the stock shifter. If it pops out of gear it maybe inside the Transfer case. the detent pins help hold it in gear and so it wont go into two gears at once. the slider maybe worn out that the shift fork rides on.
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Old 10-07-2018, 10:11 AM   #8
cadillac_al
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Re: Np203 shifter

It sounds like it isn't engaging in high range until he pulls the lever all the way back into hi lock. That could be a sticky shifter. My first 203 shifted like butter for 20 years until I broke it. The last 2 that I drive now stick badly and shift hard. I know it is only because they spent their entire life in high range. I have drowned them in Liquid Wrench or Break Away and they are useable but they aren't getting lubed completely to make them shift like butter like when they were new.

I would spray the sh*t out of it and see if the stock shifter will work until you get the time and ambition for the 2 stick mod.

When I shift into high range, after passing neutral I can feel the gears starting to engage as the trans starts spinning slower and it slides right in. I do this because I only want to go one click and not slide into lock by mistake.
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Last edited by cadillac_al; 10-07-2018 at 10:17 AM.
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Old 10-07-2018, 09:22 PM   #9
Texasz71
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Re: Np203 shifter

Drained the 203 and both diffs today.

203 drained out about half a quart of atf. *slaps forehead*

Filled it with 10w-40. The shifter actually shifts and stays in high..but the truck still wont move in high. I'll throw some degreaser in there soon and go from there.
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Old 10-08-2018, 02:00 AM   #10
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Re: Np203 shifter

The link I posted suggests the detent springs aren't doing their job. Maybe I should stop googling, reading and trying to help if people are not interested in being helped... Feel free to spend a few hundred when stretching a spring might solve the problem for nothing.
Is that the right lube for a 203? Google says no.
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Old 10-08-2018, 11:55 AM   #11
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Re: Np203 shifter

and if you got atf the input seal might be going bad on the 203 rangebox were the adapter bolts up .
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Old 10-14-2018, 05:55 PM   #12
Texasz71
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Re: Np203 shifter

Franken - i appreciate the suggestion, but my 203 does not pop out. It wont move the truck in high. Big difference.

Sweetk30- that's what I thought too. But the cover bolts weren't tight, so I figured someone put atf in it, then it leaked out.

I took the truck out for a spin again. Instructions on my visor say I can shift the t case under load. So I started in high lock, and shifted to high. It immediately limped like I shifted to neutral. I have confirmed that if I shift one more click up towards the dash, that is neutral.

So anyone have any thoughts? High is essentially another neutral.

PB blasted and degreased the shifter.
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Old 10-14-2018, 06:42 PM   #13
Chevyrestorerman
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Re: Np203 shifter

Take it to Dura-Trans Transmission shop in your town. They will fix it right. They appear to have a 5 star rating.
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Old 10-23-2018, 11:44 AM   #14
Texasz71
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Re: Np203 shifter

Tried to shift it from high lock to high while in reverse. Acted like it went to neutral.

Does anyone know if its possible to pull the shifter without removing the hump?

Last edited by Texasz71; 10-23-2018 at 06:48 PM.
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Old 10-23-2018, 06:32 PM   #15
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Re: Np203 shifter

It's pretty easy to look at it from the bottom. I was just playing with mine and it does shift a lot smoother than I thought. In neutral both levers on the transfer case are pointed straight down. When you put it in high the right side lever moves forward. When you put it in lock the left lever moves forward meaning both of them are in the forward position. I'm curious what yours is dong when it is in high. If the lever is moving forward and your truck isn't moving then it must be an internal issue (differential) and putting it in lock is making it work.
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