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Pop a TH400 PAN

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Old Jul 9, 2020 | 04:29 PM
  #1  
11971four4two's Avatar
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MOTORHEAD
 
Joined: Feb 2011
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From: minnesota USA
Pop a TH400 PAN







Old Jul 10, 2020 | 03:32 PM
  #2  
Tedd Thompson's Avatar
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From: Forest Ranch Ca.
Tell me more..... Tedd
Old Jul 10, 2020 | 07:06 PM
  #3  
11971four4two's Avatar
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MOTORHEAD
 
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From: minnesota USA
HEY TEDD
I thought I purchased a "stock" TH400
I pulled off the pan and this critter has been "modified"
I hoped that maybe a resident "expert" could tell me more by perusing the pictures
It was an automatic from the factory and now it is a manual transmission

Have a Good Week end
b
Old Jul 12, 2020 | 07:21 AM
  #4  
Tedd Thompson's Avatar
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From: Forest Ranch Ca.
Thanks Brian, I know little of these new modern cars...... Lost in the fifties ...Tedd. You all be good or at least don't get caught..
Old Aug 17, 2020 | 03:41 AM
  #5  
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RWK
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Joined: Jun 2020
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From: 40 miles from Lansing
Well glad to see a finishing nail holding the shift shaft, thought mine was the only one! thought I was looking at my picture. 72 TH400 in my 88. I replaced with a cotter pin, figured it was lost by previous mech and the nail was handy!

Finishing nail?
Old Aug 17, 2020 | 05:44 AM
  #6  
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From: central Indiana
Hydromatic used finishing nails to retain the manual shaft in the trans. They also used nails for the pivot shafts for the governor weights on the 400, 350, 700, 250, etc. GM spared no effort looking for ways to save money! I guess it was cheaper for them to buy nails instead of machining retaining pins or pivots.
Old Aug 17, 2020 | 06:18 AM
  #7  
joe_padavano's Avatar
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Joined: Mar 2007
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From: Northern VA
The "finishing nail" is factory. Most of the TH400s I've had apart were the same. The only "modification" I see in the photos is that the kickdown solenoid wire is not connected to the pass-through terminal in the case.
Old Aug 17, 2020 | 07:06 AM
  #8  
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From: Rogues Island, USA
Those two pipe plugs don't look stock. Where are the lines?
Old Aug 17, 2020 | 07:10 AM
  #9  
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Originally Posted by TripDeuces
Those two pipe plugs don't look stock. Where are the lines?
Good catch. I missed that.
Old Aug 17, 2020 | 12:21 PM
  #10  
11971four4two's Avatar
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This MUST BE REAL says
Old Aug 17, 2020 | 12:26 PM
  #11  
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From: central Indiana
That appears to be a home made manual valve body. The pipe plugs are blocking the govenor feed and return ports in the valve body. I’m guessing your also going to find a small hole drilled right above the return passage, the idea is to loop governor oil to the shift valves.

I’m curious to know what’s been done to the 2-3 accumulator and intermediate servo. I can see the pin for the accumulator piston has been removed. I can also see the vent hole in the 1-2 shift valvetrain is open, for the poor man homemade manual valve body to function that hole needs plugged, and the shift valve needs a vent ground into it.
Old Aug 17, 2020 | 12:33 PM
  #12  
11971four4two's Avatar
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From: minnesota USA
I sold it AS IS no longer own this transmission
I was tired of the external mod Guessing game

AINT STOCK
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