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Would it harm anything if I cranked It up and put it in drive/reverse with out transfer case to see if the tranny actually makes a grinding sound?
The only thing is that you may get fluid coming out the back. The governor is on the outputshaft and does get fluid pumped through it.

As far as cranking it up without the transfercase attached, I'd use 2 people and DON'T PUT IT BACK INTO PARK until the motor is off and the output shaft stops spinning. Otherwise you'll get a grinding from the park pawl and could possibly break it.

Also I don’t know what I’m looking at/for in my T-case. I see that the top of the planetary gear box looks broke(plastic piece) but I’m not sure what went there from the start.but it did get to hot as the thrush washer on top was brown/purple/blue (that torches look) All the splines look fine to me. I’m going to get a rebuild kit but I know I need other parts just not sure what they are.. please help
Going to be honest, I've never rebuilt a transfercase in my 28 years of owning these. I've always thrown in a spare unit to replace the worn one. Someone here I'm sure will look at the picks and provide great feedback. But I will say that it does look like it overheated.
 

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Fortunately, none of the metal gears/splines look damaged.

As for the picture of your shift fork, did you remove the bushings from it? Or were they already gone?

I'm meaning these bushings:



If not, then those very well could be causing your grinding. Without the bushings in place, the fork can't move the selector far enough to properly get it in gear, and it'll be grinding because it's between gears.


As for starting it up and spinning it without the transfer case in place, no that won't hurt anything. Although, as sackmann said, wait for it to stop spinning to put it into park. That's normally done by the resistance of the transfer case and tires, but that won't be there.

I'm not directly familiar with the NP-208 itself, so I'm not sure what the plastic piece on the planetary is supposed to look like. Maybe see if you can find an NP-208 rebuild writeup on line?
 

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Maybe some help in these videos?


 

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Discussion Starter #44
no i didnt remove any bushings, the fork feels jagged as well. the chain had quite a bit of slack in it but there is no wear on the inside of the case. i also dont understand if the only thing that is broke is the range fork then why doesnt it move in 2wd?
thank guys
 

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Discussion Starter #45
i maybe wrong, but the range fork holds position for 2wd 4hi 4low. what sequence is 2wd 4hi 4low? 2wd is top 4hi then is there a neutral then 4 low at the bottom?
 

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no i didnt remove any bushings, the fork feels jagged as well. the chain had quite a bit of slack in it but there is no wear on the inside of the case. i also dont understand if the only thing that is broke is the range fork then why doesnt it move in 2wd?
thank guys
Because it's not pulling and placing the gears in the proper location... so the gears are "in between".

It probably pushes the gear into 4wd therefore the forks can position the gears correctly
 

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no i didnt remove any bushings, the fork feels jagged as well. the chain had quite a bit of slack in it but there is no wear on the inside of the case. i also dont understand if the only thing that is broke is the range fork then why doesnt it move in 2wd?
thank guys
That very well could be your problem. The shift fork is simply toast. If the ends of the fork are worn and jagged, then you probably need a new fork, instead of just new bushings.

i maybe wrong, but the range fork holds position for 2wd 4hi 4low. what sequence is 2wd 4hi 4low? 2wd is top 4hi then is there a neutral then 4 low at the bottom?

This is how the shift fork works. It moves the engagement teeth up and down the splines inside the planetary. 2H and 4H use the same splines for a 1:1. Neutral is where there are no splines. Then 4L is the bottom section, which activates the 2.61:1 ratio.

Secondly, when you move from 2H to 4H, there is a second shift fork that connects and disconnects the engagement teeth for the chain. When it's in 2H, it spins freely with no engagement. When it's in 4H, N, or 4L, the chain is connected.

160497


That's ALL the transfer case does. It's a pretty simple device overall.
It's possible it's grinding because it can't get out of the neutral area. It might not be able to move the shift fork far enough to get into the 4H/2H splines and you're hearing the teeth skipping. A shift fork that's bad enough could do that.

Slack in the chain will cause it to skip while you're in 4x4. You'll feel/hear a POP and a little jolt in power, as the chain is skipping teeth.
 

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Discussion Starter #48
makes sense! its hard for me to diagnose a problem when i have no clue how something works. now all i need to do is figure out what that thing is on top of the planetary gear box that looks chewed up. its what the shift fork goes around and thats probably the reason it looks the way it does.
 

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Out of curiosity, where are you located? I have an NP-208 in my garage.
 

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Also, not sure if they can help you, but these are some pictures of my NP-208 when I cracked it open a number of years back to swap a truck tailshaft for a Bronco one. Not the most detailed pictures, since I wasn't fully disassembling it, but you might be able to make something out of it. Just keep clicking "Next"

Probably about 15 of the insides:

 

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Discussion Starter #53
yeah, i appreciate it though. i was going to buy one but 1000 bucks, i think ill just rebuild my own. unless it doesnt work then i guess ill have to
thanks bubba
 

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That definitely looks like it. Hopefully a rebuild, and some new parts, solves your issues!

If not, you don't have to stick with an NP-208. The BW-1345 and BW-1356 will also fit. Might need to fiddle with the linkage a little and splice in your 4x4 light, but that's about it. Just be sure it's from a Bronco so it has a yoke on both sides. The truck has a slip joint tailshaft (like in the pics I sent) that won't work.

Worst case, we can work something out. I shipped a transmission to New York from here. Just wrapped it in moving blankets and then bought a big tupperware bin from Lowe's to ship it in. The NP-208 is smaller and lighter than that transmission was. Certainly would cost less overall than $1000.
 

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I'll send you a PM.
 

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Do you have any junk yards in your area you can go pull one from?
 
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