208 the same as 203 or 205

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Battlac40

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It is all based on a)spline count b)tail shaft length and style, c) crossmember that fit the adapter you need, and d) the adapter you need.
Then it is time to play with driveshafts.
Chevy played with this. My 81 setup is a 350C-lockup transmission with a 208 27-spline with the flat crossmember that fits a th350 transmount then an iron short round adapter.
I want to do a 32 spline conversion to a th400 with the w-crossmember and an ORD adapter. The lockup trans has a different torque converter and a red shift vacuum. 85'ish suburban style.
 

bucket

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The crossmember styles are a year range thing, rather than a driveline combo thing. So that adds a bunch to the confusion.

The flat style crossmember and matching t-case adapter (tall foot) was gone after '84.
 

Rusty Nail

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:jawdrop:

A wild Th-350 appeared!

Hmm....

Neat lookin transfer case shifter you got there...looks kinda familiar. :Pshyco:

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Rusty Nail

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This morning's first round pictures out of Tenessee

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Ain't so unicorn, think I found TWO last night.
FOR 81-82 K5 even.
Maybe they're just nocturnal critters?

Maybe that's what I want.. Think I've got the W crossmember though. I should go look lol. I find these for flat ones? pretty easy.


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Rusty Nail

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Ya. "W" crossmember with adapter that is off towards the driver side.
That's as easy as swapping the adaptors though ... it's all about the
Long Shaft BB :

Lookit how long!

Omg that's it.

Ohhhh!
Eehhh!
Ahhhh!

AdaptEr or AdaptOr ?
Unknown. Any grammar Nazis lurking?

I asked old boy how much Output shaft was hanging outside the case...I really just want a picture of the transfer Input because he won't say "208" but pretty sure this is a comparable trans that will bolt in.

The OTHER line I'm waiting to reel in is in OKLAHOMA.
I'd rather drive a Civic to Tulsa than pay for a $250 pallet ride. ;) Maybe they'll message back.

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MANY sellers are liars or ignorant.
Its tough sorting them all out

AGAIN. choose sources very carefully.
 
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Poppy 87

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This morning's first round pictures out of Tenessee

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Ain't so unicorn, think I found TWO last night.
FOR 81-82 K5 even.
Maybe they're just nocturnal critters?

Maybe that's what I want.. Think I've got the W crossmember though. I should go look lol. I find these for flat ones? pretty easy.


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That second picture looks to be a TH400 to me
 

TubeTruck

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That is a TH400. The 400 has a finned tailshaft, the 350 does not.

TH350
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TH400
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Rusty Nail

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Mother f

I'm about to call Detroit Axle back and quit screwing around with the plethora of *********.
Not rolling a 350-C case either.

Turbo 350 is angeldy on the PASSENGER side.

Thank you men.

The pictures of the 208 shifter though?
They haven't called bak yet?
:nono: bad sign.

Stupid Unicorns sellers

*edit* they didn't call back because I never sent the message
 
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Rusty Nail

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Here's my other shot.

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Lotta spline length

That's not a 4x4 case though huh.

This is difficult and I love it

That's no different than what I'm replacing

May as well call detroit axle back and pay assloads to get a bad mother built

Trying to trade my Suburban door panels for their Blazer examples and trade for that 81 grille while I'm at it. It prolly won't fit my 88 anyway.
 
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Poppy 87

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Rusty, pretty sure the case doesn't matter, it's the output shaft length that is different for the 4x4 transmission
 

Rusty Nail

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I want to think that too but i'm not convinced it's correct. Hell. I believe that most of the readers think that and yet I carry on..
There's no question the cases changed 79-84 to include a hole for the TCC switch..surely one without a hole is better than one with a hole, used or not. An "NLU" case (non-lock up) is a th-350 case but superior to a th-350-C case. BUT there was such a thing as a heavy duty 4x4 case?

I find speak in more than one place about additional material and even INTERNAL WEBBING. :disgust:

If you want to BUY a Heavy Duty 4x4 case, Detroit Axle said that case runs $800.

For the case?
Pix?
Nope- it's special order. No ****.

Most run about $300 for a real 4x4 case and is said to be much more beef towards the output.
I think that a "9 inch 4x4 case" was found in bad ass K trucks and looks kind of like a 700, with a long snout like that and maybe that is the right deal to want. To make into a 12 inch though? Yes. I need a 12 inch th350.
So i think you want to find ,(partial vin,)a 4x4 truck, OEM with a 9 inch case, (pre 79 NLU case) but then u gotta take it apart and put the long output shaft in it to make it a 12?
There really is such a thing as a th-350 case with a factory six bolt torque convertor cover.. that happened? Pretty sure, i've seen one.

ONE.

Every day I wake up and think I know WAY too much about 4x4 th350s and every day I learn something new.

Not just one thing though, several.

I cant barely talk about em anymore. I guess that scares the peewaddin out of these poor builder cats or maybe they THINK im stupid man but thats a LOT OF NUMBERS for there to be no variance.

There has got to be at least three OR FOUR th-350 cases not including variations of th-350-C cases...
They even have three digit letters cast on em.
Separately there is such a thing as a "CBC" Chevrolet-Buick Combined case and everybody knows about B-O-P cases but I think the CBC case is both BOP AND Chevrolet surely it MUST have additional material. Two different things.
Three to count a chevy case and THOSE had three different letter combinations on em.

We're talking MILLIONS OF CASES man, 69-84....you don't really believe they are all created equal? 6,9, or 12s

Some have partial vin #s, the plant they were stamped at, there's something specific about OLD cases and the difference between AC and NON AC vehicles.
All of us squarebody guys know AC trucks were built with heavier duty options.

Thats a bunch of stuff im willing to learn about but as usual, finding one definitive source of information proves very tough to pin down.
Most people consider them all the same but they simply aren't.

There are many different ones in reality but then again, i know way too much about it sometimes to not be able to tell you WHICH IS the better one.

The second you start tellin muggs u want a CBC case? Their eyes roll in their heads. After you explain it to em..... its just gotta be stronger!

I quit doin that already. Haha. I'll never get one built at that rate..:(

Everyday that passes this rabbit hole gets deeper and deeper.
Who knows where it goes?
It may all be ******** though. I guess.

Its as entertaining as it can be, to me, see?

I dont think the trans for a 6 cyl base (noAC) Nova is the same as a heavy half or big ten Silverado case, whatever. Surely not, agreed?


But srsly, partial vins?
Im out on thag ones. I want to know enough about it to make an informed decision since im going to the trouble.

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There is a correct answer about which is the BEST one, but I dont know what it is. Yet. Lol
As soon as I learn enough about it i'll settle on something. Right now i'm enjoying all this digging.
:(
I know way too much about it.
Progress halted Thursday at noon.
I know that for sure :)
 
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Rusty Nail

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Here's some pictures of a lock up CBC case

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Never knew that huh?
Ya, most people think they're all the same..
No offense intended friend, we're all learning in this thread.

Compare yours to that factory beef lol.
 
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