Converter UN-lock switch

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BigB82789

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I searched here and some other sites and can't find how to do it. I have a 2 pos. lock up switch, but I'd like to have a 3 pos. so I can force the converter to unlock. What do I have to do besides a ground (forced lock) jumper, and the tapped wire?

Also, anybody know how to wire a forced O/D switch in a 47re?
 
I drew you up a diagram real quick.

You have to cut the TC lockup wire from the PCM completely in half to do this. I think my diagram will explain the rest, but let me know if you need to know anything else or a better explanation.
 

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Usually when you are pulling you wont be going fast enough for the factory system to lock the TC. So if you have just a TC lockup switch, you can just flip it off, and it will unlock anyways without "forcing" unlock.

Normally a forced unlock isnt needed for anything, but sometimes you may want to force unlock say if you are towing, and you need a few RPM's, or dont want to lug the motor. Say you are going 50mph in overdrive taking off with a load, and the TC wants to lockup at that MPH. It will lug you down to 1400rpm or so, and you would be better off running unlocked until you got to say 60mph or so. This way you can force unlock until you are going the desired speed, and then let it lock.

Also, on a stock transmission, the stock converter will take a lot of abuse unlocked, but when it is locked the converter clutch wont hold much power. With a forced unlock switch you can force it to stay unlocked and you dont have to worry about slipping the TC clutch.

There are several reasons a person might want one, just depends on the use of the truck.
 
Sled pulling on the big end.
Brandon
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That, and when ever its goes to over drive I want the converter un locked until 55 or so. With 4:10 gears it will go into O/D at 40 mph and stay there lugging it down to 1200 or so. 3rd gear with 4:10 gears is too high of a cruising rpm at 45mph..
 
Usually when you are pulling you wont be going fast enough for the factory system to lock the TC. So if you have just a TC lockup switch, you can just flip it off, and it will unlock anyways without "forcing" unlock.
Click to expand...

Mine doesn't do it all the time. I've been drug down by a hard hitting sled where its just too fast for the computer to react...
 
BigB82789 said:
That, and when ever its goes to over drive I want the converter un locked until 55 or so. With 4:10 gears it will go into O/D at 40 mph and stay there lugging it down to 1200 or so. 3rd gear with 4:10 gears is too high of a cruising rpm at 45mph..
Click to expand...

yea my truck is the same with 4:10's

what stall is your converter??
 
This one will unlock when you hit the brakes or you can hit the switch the convertorI have used this a couple of time and works realy good.

AutoMysterypictorial.jpg
 
Ok, what color wire is the TC wire? I have the forced O/D switch done, but I'm not sure where the wire is and goes for the TQ converter.
 
orange with a black stripe......you can find it on the pass. side of the truck toward the top of the firewall.
 
IIRC, there are 3 connectors that go to the PCM......I think the middle plug is where you find the orange/black wire.
 
Thats the one for the lockup isn't it. I think I have taht one. I need the one for the unlock.
 
I guess I'm not following you.
Whatever kind of set-up you have, once you get it all wired up, the only wire that it needs to hook to is the orange/black wire. That wire controls the lock/unlock of the TC.

Unless I'm just not on the same page with ya.
 
I'm talking about the wire in the very first diagram at the begining of this thread.

I had just a lock-up switch before, and I have it tapped. Then I run a wire from the tap to the switch, and a ground wire to the switch. But that is only for lockup, not unlock.

Are you saying I have the wire already, I just need to cut it and run on end to the switch and the other to the switch as well?
 
Are you saying I have the wire already, I just need to cut it and run on end to the switch and the other to the switch as well?
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Yes, you already have the wire (orange/black).
Hook it up like the diagram in post #2. One end will go from the plug (PCM) to the switch and the other end will go from the switch to the trans.
You will cut the wire in two, doing away with the wire tap.
 
yup you route them both to the switch so you can interupt the signal completely when desired.

Joe
 
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