TH400

Donald

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I have a TH400 in my 31 Chevy pickup , the trans has a 4 pin weather pack style connector . I have never seen a 400 with more then 2 pins . Did GM have a lockup convertor ?
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nvrenuf

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No lock up, kick down and reverse are the only wires I can think of. How sure are you it’s a 400?
 

Vbb199

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Sounds like it's a 700r4 in there.

Does it have a big round cover about 4" on the passenger side of the trans?
 

AuroraGirl

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I have a TH400 in my 31 Chevy pickup , the trans has a 4 pin weather pack style connector . I have never seen a 400 with more then 2 pins . Did GM have a lockup convertor ?
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Are you sure this isnt a
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One of these guys. Im guessing early 4l60e unless the PN switch wiring is on the external switch and this is the wiring going into the case
 

Donald

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Yes it is a. 400 I worked for GM dealers and rebuilt many 400's .It is a metric trans at least the bolts in it are .The connector AuroraGirl has pictured is what I have . I think this trans is from Monster transmission , they must have used that instead of the correct one . Looks like I will have to pull the pan and check the wiring .



at
 
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Vbb199

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OK now you got me interested. What motor is in the 31?

I know the th400 was used behind other mfgs like Chrysler, Ferrari, Rolls Royce, and I think also jaguar
 

Matt69olds

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If your absolutely sure it’s a 400, someone has swapped the case connector. I have used the single wire 400 case connector on 700 swaps, I suppose the case connector would interchange the other way. Since it didn’t come stock that way, you will need to drop the pan and figure out what has been done.

Every 400 has a kickdown solenoid, some had a pressure switch on the 3rd accumulator passage on the valve body for transmission controlled spark (basically delayed spark advance until the car was in 3rd gear) the early BOP 400 had a switch pitch (basically a 2 speed converter) so at most you would need 3 wires. Since Chevy never had the switch pitch converter, and I seriously doubt you have functional spark control, a single wire connector is all you need.
 

AuroraGirl

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OK now you got me interested. What motor is in the 31?

I know the th400 was used behind other mfgs like Chrysler, Ferrari, Rolls Royce, and I think also jaguar
fun fact, BMW used a 4l30e
 

Donald

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The 31 has a 350 with aluminum angle plug heads , Edelbrock dual 4 air gap manifold of course Edelbrock carbs , MSD ignition and box . TH400 and a Richmond quick change rear . By the way thanks for the input . Don
 

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AuroraGirl

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I admire the type 2 / TC saginaw ps pump, as well as the delco cs130 alternator, but if you ever want more power or just a better alternator, you can get an ad230 in the same ear setup and also chrome/shiny and the pulley would go on it, allowing it to take its place. the wiring is 1 to 1 adaptable or repinnable. They also make 1 wire versions
 

Donald

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I would like to use a AD230 but the power terminal is in the back of the unit and would hit the cylinder head , I have no clearance at all , the back of the alternator is a 1/4 inch from the head .
 

Rickf

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I am curious about the steering & front clip/frame.
 

Donald

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The 31 truck has a TCI independent front end with a modified stock frame . If you are asking about the 85 it is a stock front end with 3" dropped spindles and a coil cut out of the springs , rear is C notched and flipped axle .
 
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AuroraGirl

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I would like to use a AD230 but the power terminal is in the back of the unit and would hit the cylinder head , I have no clearance at all , the back of the alternator is a 1/4 inch from the head .
you can use a remote-rectifier bridge and then use about any alternator you want
 

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