Anyone here ever tear down / rebuild a 208C transfer case?

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Doppleganger

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I never have. Got this one apart and know someone was in it before as there were shards of silicone and old needle bearings throughout, plus clips and lock rings missing. Got (what I know was missing) it all replaced but how it was assembled does not match videos or diagrams of a 208 overhaul.

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Nowhere is this thick washer/spacer, the dowel pin or the thick snap ring shown, but here it is on mine. This is a big deal because everything out there shows the main shaft going in first, then the gears with chains, being laid in as a whole. This washer and snap ring wont allow it to go back together that way.

ANY ideas?
 

shiftpro

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Get a 205.


(sorry couldn't resist)
(oh and big block)
 

Joshua Keith

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@Doppleganger I don’t have any personal experience, but I did just YouTube NP208 rebuild and a ton of videos came up.
 

Doppleganger

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@Doppleganger I don’t have any personal experience, but I did just YouTube NP208 rebuild and a ton of videos came up.
I know - and none of them show this. The diagrams are vague and the manuals are semi-worthless. I have seen videos for 208's in Fords totally different.

I'll figure it out - was just hoping someone had done this before.
 

Camar068

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never been there before, but I do see the washer, jesus clips, and dowel pin in this video at 11 seconds. Don't know if it's possible, but could the gear need to be flipped around? Sorry thinking outside the box and trying to help.

xc_hide_links_from_guests_guests_error_hide_media
 

Doppleganger

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That end of the main shaft I have all set. Its the back half that has a very thick lock ring that I'm not 100% sure on.

Just found out also that the brass synchro ring is also missing. I have read some dont need it but also found they all came with it, so someone hacked this for some reason.

Its one thing to take something apart and overhaul it when you never did one.....another when items are missing so no idea where or how they originally went.

Thanks for the help though.
 

59840Surfer

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I just resealed my 208 a couple of months ago. I had to manufacture a new High-Low fork, but it was worth it - parts aren't available unless you buy a whole unit. I didn't want to do that - so I fixed what I have.

There is no brass synchro/clutch ring in this unit.

That pin and circlip on the shaft indicates that you have straight cut planetary gears.

Can't be totally sure, but I believe the 400ci SBC engines had the helical cut reduction gears - which I gladly traded out of a Jeep Grand Cherokee for their "noisy" reduction gears and output shaft (they are a pair) and gave him the helical gears.

He was happy - I was happy.

My '86 K5 had a 400 SBC in it when I got it and it had a cracked block and head so I got rid of it for a stroked 350-383 SBC conversion.

Somehow I believe that the 400 SBC had less power than the 350 SBC engines and GM put different gears in them --- not 100% sure but I've seen this a few times over the years.

Anyway - I've never had any real troubles with this transfer case - not mechanically, but it did develop a leak after a while between the transmission and the transfer case and they were swapping fluid.

So I pulled it and resealed it nice and easy. (not really!)

At that time I found the High-Low fork had gone bad - not bad enough to fail - but it was close because the plastic slipper shoes were gone and the fork was grinding on the slider.

I could not find a new or good used fork in Montana so I just rebuilt it with arc welding, grinding and then overlaying with brass where the slider pads had been.

After some Dremel work and a high speed die grinder was used - I got it nice and tight again and this time it will not wear out.

BTW: these units do NOT have oil pumps - they are overfilled so that everything is covered in ATF all the time.

It works!

If that was the only good point about these units (no pumps to eat through the case) ---then I'd use them forever but I now have 2 more GMs with those Auto/AWD-2H-4H-4L things that I don't want to get in to forever!

Sorry I didn't take any pixs or vids - my bad.
 

59840Surfer

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Found a drawing of that shaft and short pin ......... Part #23.

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#26 is the fork I rebuilt.
 

Doppleganger

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Regarding the leaks.....heard a guy mention this stuff (I had never heard of it before) but it seems to be the bees-knees of diff and gear box sealants. He mentioned never to use Ultra Black with a transfer case or diff - my case was full of black silicone chards from the PO messing with it (and using ultra black). I've also had an ongoing issue with my diff cover I'm going to try this on.

https://www.permatex.com/products/g...matex-gear-oil-rtv-gasket-maker/?locale=en_us
 

59840Surfer

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I usually use the Permatex RTV Copper or Red for these jobs.

The gasket between the adapter and the transfer input case area is a joke! That's the best use for RTV 'cause the surfaces are never really gonna seal by using a gasket alone!

I know -- BT - DT.
 

Doppleganger

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That end of the main shaft I have all set. Its the back half that has a very thick lock ring that I'm not 100% sure on.

Just found out also that the brass synchro ring is also missing. I have read some dont need it but also found they all came with it, so someone hacked this for some reason.

Its one thing to take something apart and overhaul it when you never did one.....another when items are missing so no idea where or how they originally went.

Thanks for the help though.
I figured out that the PO had been into this case before and had put the snap ring back in the wrong groove. It took several pics of freshly opened boxes (online) to figure out where the ring went and what direction the gear went also (there were slots on one side, so it was also upside down).

After sorting the mess out, all I can say is I'm thankful I never had the truck running long enough to even try 4WD. I probably would have broken or blown something up....had it even been semi-functional.
 

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