NP 205 Rebuild and Info

[Mt Man Chad]

Great job on the write up, Thanks!
Is that a stock shift bar, looks a little different than my stock one?

[madcow75]

there are I think 2 different types.

[jerry moss]

i just added this to my "favorites" list.
great info, thanks a bunch. you are doing some awesome work.

[D.PASSMORE]

Can you recommend a good (not chinese-) rebuild kit? Where to buy?
Good stuff, I'm just starting on a rebuild.
Thanks DP

[tdkosta]

Great thread thanks a ton

[JPalmer81]

Thanks a ton, i will be using this this winter when i do a sm465 and np205 rebuild!! Invaluable!

[swclassics]

Awesome thread, thank you!

[jbclassix]

I'm glad that everyone appreciates this thread! I guess I should let everyone know why I haven't installed the yokes and adapter yet. Some of you may know that in September I was in an accident during my move from Colorado to California. Unfortunately I was unable to tow the trailer with all my stuff in it the rest of the way, so the trailer, and everything in it, are in storage in Colorado. The t-case, the suburban it goes in, all my shop tools, everything.

Hopefully I will get out to CO this year and finish this up for all you!

[obijuan]

since the 205 is super common and this is a good resource ill add what i know to be true. please feel free to add your input.
keeping this to 69-72, 73-87/91 big body pickups


ALL crew cabs were fixed yoke.
regular cabs with carrier bearing were fixed yoke.
post 1985 np205 regular cabs are slip yoke.
all 1980 tcases were 205s. most slip yokes.
all rear output shafts are 32 spline. fixed and slip.
both slip and fixed yoke can be swapped with just removing the 8 bolt housing and removing as an assembly. also between chevy ford dodge and international. speedo and breathers just change.
vss introduced in 1990.
all 205s were figure 8 front pattern until 1985.
1985 introduced the round pattern 205.
i think 73 the speedo cable moved to passenger side.
several assortments of shifter styles.
1985 also introduced the W and S crossmembers to be used with short adapters and one piece rubber mounts.
pre 1985 one ton 205s had a flatter crossmember than 1/2 and 3/4 tons.
pre 1985 1 ton crossmembers went INSIDE the rails.
pre 1985 1/2 and 3/4 tons went below the rails.



the common/early sm465 version of the 205:
figure 8 pattern face
ten spline input male
small input bearing
ten spline front output if it has the spicer CV.
30 spline front output for the later flanged cv front driveshaft.
uses the taller two footed adapter

the other/later sm465 version of the 205
found post 1985
round pattern face
32 spline female input gear. with the BIG bearing case.
LONG input gear, around 4". not short th400 style.
30 spline front output flanged
uses the short foot adapter with one piece rubber mount


th350 version
27 spline male input gear.
small input bearing
figure 8 pattern only offered.
tall adapter.
can be used to put behind a 700r4.


early th400 version
figure 8 pattern face
32 spline short input gear, 2" ish.
large input bearing
strongest for offroad applications especially doublers


later th400 version
found 1985 and newer
round pattern face
long input gear same as later 465 version.
same large input bearing
30 spline flanged front output.
this is what you want for putting it behind an nv4500.
use a pre 1985 short th400 input gear if you dont want to use the advance adapter spacer. but thats a whole nother can of monkeys.

4l80 version
1991 only
round pattern face
large input bearing
does not share same adapter as th400.
has its very own adapter
same long input gear
VSS


ford international and dodge np205
they have a 32 spline front output shaft
these all swap over to GM cases to enable larger/better yokes to be installed.

[obijuan]

On the transmission side of the adapter there is a groove for a rubber o ring.
Posted via Mobile Device

[jjzepplin]

There are also two regular type seals that are in the adapter for the coupler outer seals. The inner is the o ring. This keeps fluid from your trans from going into your t-case.

[jbclassix]

Originally Posted by jaros44sr

Is there any info. on the seals and how they are installed for the adapter that bolts to the trans? Seems this is where mine is leaking

Help?

Thanks for taking the time jbclassix

On this one that I built there is an o-ring on the input shaft of the t-case that seals to the inside of the adapter sleeve, and there is a plain encased seal in the adapter housing that seals to the outside of the adapter sleeve. I am going to finish rebuilding the t-case soon.

Originally Posted by jjzepplin

There are also two regular type seals that are in the adapter for the coupler outer seals. The inner is the o ring. This keeps fluid from your trans from going into your t-case.

[jaros44sr]

Sounds good guys, thanks for the help

[jbclassix]

Wow. 2 years later...

Tips for the Yokes. I sleeved both. I use green lock-tite on them to prevent seepage between the parts. i apply RTV sealant to the inside of the yokes, and not the shaft. This way you will not be pushing RTV into the case.
10 spline front yoke repair sleeve part number (federal mogul 99174)
32 spline rear yoke repair sleeve part number (federal mogul 99212)



Spline washer seal. important piece. Only works on the 32 spline yokes in my opinion.



Torque for the rear yoke is 150lbft.

repeat steps for the front yoke. The front has a dust shield.







I will show pictures of the early style adapter for reference.

[obijuan]

The 205 is one of the easiest things ive ever done on an r&r. I have done, nearing 15 of em id say, for people afraid of em. Its just parts. Same thing with a th400. Take it apart. See whats inside. Youd be amazed at the simplicity.
Posted via Mobile Device

[FRENCHBLUE72]

Do you happen to have any pics of the adapter seals? Mine is the o ring style on the trans to adaptor and idea on the case to adaptor seal? My trans was leaking atf into the t case so here I am..

[jjzepplin]

Auto Zone had mine in stock. They look just like wheel seals and the coupler just sits centered on them. They seal the outer part of the coupler while the inner is sealed by the "o" ring. Case to adapter gasket can be bought on ebay for a couple bucks.

[obijuan]

Posted via Mobile Device

[obijuan]

Those are the three seals you will need. Small oring is for the inside of the coupler. Big oring is for the trans to adapter. Regular lipped seal is outside of coupler.
Posted via Mobile Device

[FRENCHBLUE72]

I found all the seals with the exception of the small o Ring seal to the shaft
Posted via Mobile Device

[obijuan]

Comes in my gm 205 gasket kits.
Posted via Mobile Device

[jbclassix]

I have 2 lip seals in my adapter. The larger one obijuan doesnt have pictured i cannot find a PN for. For autos i recommend putting some silicone on the inside of the coupler like i did the yokes.
Posted via Mobile Device

[jbclassix]

Here is what I have for seals.

there are 2 lip seals inside the 1st gen adapter.

here are the 2 lip seals.

transmission side


transfer side


here you can see where the 2 lip seals ride on the coupler


here you can see the sealing surface the o-ring on the t-case input shaft seals against. Make sure this side of the coupler is on the t-case side. Also, clean the splines on the coupler, and put some silicone on it. This will act as a back-up to the o-ring.

[jaros44sr]

Thanks for the added information, should come in handy....

[jbclassix]

Bad image of 32 spline front output shaft