TH350 to NP208 install questions

scenic760

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Hey All,

I'm going to use the long weekend to finally put this thing back together!

I'm dropping then the engine in with the TH350 connected to it which was a bit of a game of Tetris for sure but I finally got it sitting right where it should in the engine bay. I have the cherry picker just barely holding the engine off the motor mounts at this point to move it back to mate the case and transmission.

The problem I'm having is getting the transmission to draw up to the transfer case. I wiggled it around a bit at the start and got it to go in about halfway using a ratchet strap which ended up breaking on me (Harbor Freight so not really a surprise) but it looks like it's hung up the last 1 1/2"... not sure if I need to just winch it harder or it's hung up on something trans to trans?

Anyone have any ideas what might be holding it up?
 

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bucket

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Whoa! Don't winch it up on there! You seem to have the wrong (too long) output shaft in the trans! What was the trans from originally?
 

scenic760

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Hey Bucket!

So both the trans and case came off the truck originally and I personally pulled them apart...I didn't change any of the shafts/inputs during the rebuild..

The one thing I forgot to mention is that the reason I was winching it to mate it up is because I couldn't get the cherry picker any closer!

I was trying a jack underneath the transfer case to mate up the angle and thought that might have something to do with it?
 

bucket

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You for sure have a 205, and not an aluminum 208?

I know that shaft is too long (lack of splines at the flange) to mount up an np205 without the use of a spacer.
 

scenic760

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You are correct, it's an NP 208...let me change the title of the thread!!
 

bucket

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Ah ok, that makes more sense then!

At any rate, it should be able to mate up completely without forcing anything. You may just not have the right "angle of the dangle" going on. You may have to "hold your tongue just right" when you are installing it too.

You may want to pull it back off and make sure the splines haven't got a buildup of rust.
 

scenic760

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Thanks again Bucket!

So I'll try to just barely take the tension off the motor mounts and wiggle it in there...I did realize there isn't any tranny goo on the spline so that may be making it difficult?

it looks like it's 1/2 way in there though? From memory there shouldn't be anything structurally holding it up at this point?

I took it out of gear to move the spline around to get it to slide in initially....should I put it back in park?
 

scenic760

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Hey all,

So after trying to scour the internet for any videos for ideas about drawing the engine/tranny to the case without much luck, does anyone have any "best practices" to get that done?

I have the transfer case installed with both the front and rear driveshaft in, the engine tranny are mated up and sitting on the motor mounts about 1" forward of the mounting hole alignment... there is a decent amount of resistance I would think trying to slide the motor/tranny into place with it sitting on the mounting towers?
 

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First off, you should have the engine and transmission mounted and should be trying to bolt the transfer case up to them, instead of the other way around.

Second off, pull your driveshafts off and I guarantee it'll slip right together. You're just making it as hard as possible on yourself lol.

Lastly, i would probably put it in park and then try and rotate the transfer case output to match up the splines. And no there is nothing in between other than the shaft that would hold you up.
 

scenic760

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First off, you should have the engine and transmission mounted and should be trying to bolt the transfer case up to them, instead of the other way around.

Second off, pull your driveshafts off and I guarantee it'll slip right together. You're just making it as hard as possible on yourself lol.

Lastly, i would probably put it in park and then try and rotate the transfer case output to match up the splines. And no there is nothing in between other than the shaft that would hold you up.

Hahaha....apparently I just like wrestling with transmissions and transfer cases while lying on concrete!!

I got lucky and as I was climbing under thetruck with a wrench to take off the drive shafts, I moved the jack under the tcase and your right, it slipped right in!

Couldn't have done it without all the sideline support!! Thanks again all!
 

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