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Old 12-19-2019, 12:29 PM   #1
SunSoaked
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Th400/205 question.

I've decided to put a GV behind my Th400. I'm still going to swap out the factory (85 K20) np208 32 spline case for my NOS 205 round pattern case. The 205 has the long input shaft.

Before I pull things apart I need to know if the 205 will bolt up to the 400. I know the bolt pattern is the same, I just don't want to have to change to a short input shaft after I begin tearing it apart.

I can't seem to find if the 208 stickout is the same as the long 205?
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Old 12-19-2019, 02:29 PM   #2
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Re: Th400/205 question.

Just swap the input of the 205 to the short 32 and cut a small notch in the adapter for the 205 upper shift rail. You'll also need to make a bracket for the shifter handle as the 208 adapter will not have the hole for the 205 shifter. Otherwise, you'll swap the output of the trans and find the correct 205/400 adapter to keep the long input
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Old 12-19-2019, 03:34 PM   #3
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Re: Th400/205 question.

I was hoping you'd chime in kw.
So if I don't want to swap input shafts can I use an adapter to make up the difference between the long & short shafts? Im guessing somebody makes one. It should be no different than the AA adapter I currently have between the 4500/205. It's 1.625 thick. If it's less than that I have easy access to a mill. That adapter has the notch already in it. I'm also using ORD floor mount twinsticks.
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Old 12-19-2019, 08:15 PM   #4
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Re: Th400/205 question.

OOOO... you're gonna love the TH400/NP205 combo with a GV! Bomb-proof combo!

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Old 12-19-2019, 08:43 PM   #5
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Re: Th400/205 question.

Your giving up the od in the nv4500 for the t400....hows that gonna affect your highway rpm?
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Old 12-19-2019, 10:52 PM   #6
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Re: Th400/205 question.

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Your giving up the od in the nv4500 for the t400....hows that gonna affect your highway rpm?
Ummm...the Gear Vendor OD. I want to install my twin stick round pattern 205 when I put the GV in, otherwise I order a GV for a 208.
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Old 12-19-2019, 11:42 PM   #7
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Re: Th400/205 question.

I see I see....I saw gv but it didnt click as to what you meant...then I saw 4500 in the other post....somewhere between the 2 I thought you were swapping a NV for a t400...my bad
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Old 12-20-2019, 01:22 AM   #8
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Re: Th400/205 question.

Quote:
Originally Posted by SunSoaked View Post
I was hoping you'd chime in kw.
So if I don't want to swap input shafts can I use an adapter to make up the difference between the long & short shafts? Im guessing somebody makes one. It should be no different than the AA adapter I currently have between the 4500/205. It's 1.625 thick. If it's less than that I have easy access to a mill. That adapter has the notch already in it. I'm also using ORD floor mount twinsticks.
Don't know of anyone making an extension adapter. Maybe AA has something, but I doubt it
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Old 12-20-2019, 12:14 PM   #9
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Re: Th400/205 question.

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Originally Posted by mongocanfly View Post
I see I see....I saw gv but it didnt click as to what you meant...then I saw 4500 in the other post....somewhere between the 2 I thought you were swapping a NV for a t400...my bad
Lol. No problem. I've done it many times.
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Old 12-20-2019, 01:50 PM   #10
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Re: Th400/205 question.

FWIW to someone that may run into the situation I have.
I asked the good folks at ORD about my dilemma.
Response:
You have three options:



Swap the shorter 32 spline input in, notch the adapter for shift rail clearance and bolt it up. The 208 adapter doesn’t have a threaded boss for a shifter to pivot off of.



Use this spacer:



https://www.offroaddesign.com/6-bolt...-hardware.html



and it would bolt up without tearing the 205 apart. Same hurdle with no shifter boss.



The third option would be the stock ‘85+ TH400/NP205 adapter, that would bolt up without mods and does have the threaded boss for the shifter. But they’re rare, only available used and we don’t have any.

So this is great news! That is the same exact adapter I have laying around although mine was from AA and used to bridge the gap between a nv4500 and long input 205.

The issue with the missing shifter pivot boss for the 205 is a moot point because I have ORD's Floor Mount Twin-Stick shifter.

Killed two birds with one stone with zero $$ spent.
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Old 12-20-2019, 06:12 PM   #11
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Re: Th400/205 question.

Sweet...ord is great to deal with..
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