Can you run a 700r4 WITHOUT electrical connection?

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82sbshortbed

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I just had one installed in mine. If I remember correctly my lockup is vacuum controlled. He said they sent the wrong electrical kit. So he gave me the correct pn and I ordered it. I'll be corrected if I'm wrong. Any vacuum lines to it?
 

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The check ball in the converter clutch solenoid SUCKS! There is no way to control the converter clutch. And since a 700 is hydraulically capable or locking in 2nd gear, I bet if you do the check ball modification it will lock instantly after the 1-2 shift. The truck won’t like that.

If you want the lockup converter to work, it’s really pretty easy and cheap. I’ll find the part numbers for the pressure switch you need.
 

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I just had one installed in mine. If I remember correctly my lockup is vacuum controlled. He said they sent the wrong electrical kit. So he gave me the correct pn and I ordered it. I'll be corrected if I'm wrong. Any vacuum lines to it?
No vacuum lines I can see, but there is a fitting on the very top with a hose that hung over the side that’s connected to nothing. Figured it was a vent??? Seen in the pics above.
 

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If you want the lockup converter to work, it’s really pretty easy and cheap. I’ll find the part numbers for the pressure switch you need.
My trans doesn’t have any pressure ports for a switch. Not sure if all years have them or not.
 
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Ricko1966

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@Matt69olds not challenging,inquiring I did the checkball on my truck and was happy with it. Do you know about this screenshot Im putting at the bottom? What year was the change? And I totally agree a little wiring and a 4th gear pressure switch would be cheap and easy. At the bottom of post 5 I saidvI think all he needs is a pigtail and some help with the wiring. But my curiosity is really up now with the check ball what years does it work?
 

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Ricko1966

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AuroraGirl

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I'm guessing this was a 1973 with a 250/6 and a 3 on the tree that someone put in a 700r4 behind a buick 455. In which case there is no pigtail. Give us some more details I'm sure we can walk you through this.
I had misunderstood rickos reply as OP talking and also missed the snarky, but real, felt attitude lol!
 

Ricko1966

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K
 

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Matt69olds

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My trans doesn’t have any pressure ports for a switch. Not sure if all years have them or not.

Every valve body should have a pressure port for a 4th gear switch. Some have one for 3rd.

The switch has a blue arrow pointing it out. You won’t be able to fit a socket on it with the 1-2 accumulator housing in place, you will have to use a pair of slip joint pliers to remove/reinstall.
 

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Matt69olds

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@Matt69olds not challenging,inquiring I did the checkball on my truck and was happy with it. Do you know about this screenshot Im putting at the bottom? What year was the change? And I totally agree a little wiring and a 4th gear pressure switch would be cheap and easy. At the bottom of post 5 I saidvI think all he needs is a pigtail and some help with the wiring. But my curiosity is really up now with the check ball what years does it work?

Ah! I forgot about the early 700 with non electric converter clutch.

I friend of mine bought a REALLY nice tubbed 55 Chevy with a stout 400 small block. The engine had a dyno sheet showing 480hp, with the rowdy cam one would expect. The 700 in it had the check ball in the converter solenoid. With the radical cam, the car was uncomfortable to drive around town. It would lock the clutch as soon as it shifted into 2nd. The car would buck, jerk, stumble, the engine would ping, and didn’t drive the way a nearly 500hp car should.

I suppose if you had a light car, with a decent amount of low end torque, it might not be a bad solution. Not in that 55.
 

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Ok guys

I saw examples online of guys adding pressure switches to the exterior of the transmission, and thought that’s what y’all were referring to. Sorry.

I guess this trans already has a pressure switch inside from the factory. It just wasn’t working obviously as no wiring was connected to the outlet on the drivers side. That’s what I need to address once I get it rebuilt and reinstalled.

I’ve got the 4 pin harness ordered. Just need to figure out how to wire it up, and when to turn it on/off.

Gary
 

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Use the internal pressure switch read the article I hot linked in 1 of my first posts it will tell you everything. It is the post right you said you didn't think you had a pressure switch. It is post #22
Here's some more reading for you about operating a 700r4 without a lockup convertor,I have no idea why you'd want to. But transgo does make a kit for doing it.
 
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Juancho805

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In my experience that mystery plug looks like it could belong to an oil pressure switch for a gauge or dummy light, I have seen them with both styles depending on the vehicles options. And as a technician our job is to repair a vehicle to “like new” conditions or better, so in my opinion I would recommend that you connect the required components to have a functional torque converter lock up. My 85 K10 Blazer has one of these valves on the firewall for the lockup. And here are some resources to help you if you decide to conquer the task.
 

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how did they put a 700r4 behind a 455 buick , did they adapt the bellhousing? The 700r4 didnt come in BOP
BOP = Buick, Oldsmobile, Pontiac

GM's lineup went from least $ to most $ Chevrolet, Buick, Oldsmobile, Pontiac, Cadillac. At some point they began using a lot of common parts in the BOP models with Chevy and Cadillac on their own.

By the 1980's GM had stopped making the different BOP and Cadillac engines so everything used Chevy engines.
 

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