Lockup torque converter switch. 1977-78

[Jesuschrystler]

I have a trans on my slant6 from what I believe is a 77-78 1/2 ton 2wd long bed Dodge truck. The parts truck was crushed so no way of confirming. I have a round 3 hole/2 wire, plug that came off the trans on the drivers side. I was told and I checked the part #s and I got that it was a lockup torque converter trans. How do I get this switch to work and/or is there a bypass where I can use it and not hurt it even if I don't hook it up.What or where does it go to and can I rig it to work somehow? Any ideas or links??? I cant find the site that had all the trans serial #s, I guess it shut down.

[Rodger]

Corbett

You may confirm the correct Transmission Model, other ( all ) vehicle
usages and every other thing one would want to know by coping the number
stamped into the side of the Transmission. This is located on the Driver's
Side above the gasket for the Transmission's Pan. Most of the time Truck's,
Car Towing Packages and some other usages did not have the Lock-up
feature.



Rodger & Gabby
COS

[Jesuschrystler]

Rodger, the # on the drivers side is: PK40583311-6507-5904 I know the last 3 numbers are 904 but its not a 904.It has the 727 pan and not the 904. The truck I know for sure was a 1/2 ton longbed. slant six w/auto. It possiby had a towing pkg. It was the original trans. I was told and loked on the vin# and the 6th number was a 8 and I knew it wasn't 68 or 88 . See if this helps.

[soopernaut]

1978 was the first year for a lock-up torque converter in the 727.

Does your wiring have the correct connector for this transmission? I've heard of installing a switch in the wiring to control the lock-up feature. The lock-up disables when the brakes are applied and a switch in the brake light wire tricks it into thinking the brakes are being applied(Maybe). All the information about disabling this setup seems to be for newer electronically controlled transmissions with overdrive. Also the transmission will run hotter without the lock-up enabled. I'm sure it would be easy to disable in a non-computer controlled transmission maybe you would have better luck searching the internet than my quick search. You could also get another transmission as they are cheap.

[Jesuschrystler]

Do I just hook up the switch to a manual toggle or something? It only has 2 wires. I looked it up (thanks for the link slantsix.org) its a 79' 727 long tailshaft.

[soopernaut]

Do I just hook up the switch to a manual toggle or something?

Thats what it sounds like. I have absolutely no experience with this. Most of the Sweptliners here haven't had to deal with this. Maybe a site that deals with newer vehicles would be of more help.

[Jesuschrystler]

Sorry, the truck and all vehicles I mentioned here were dodge trucks. All the parts were off a Dodge truck and/or a sweptline so I thought this would be the best place. I posted some on slantsix.org and I think I have the info I need. Again, I didn't mean to post a irrelevant thread. I will be more careful next time.

[Rodger]

Corbett

I feel it is Ok to ask what you did to both sites. The Slant Six Site has
user's that mostly think of Car Division items and you asked a Truck Question.
This Dodge Truck Site is of an era that did not have Lock-Up Transmission's.

The Slant Six 727 Lock-Up Feature is a only car item. Not for truck's, performance
car's ( also Police, Taxi and Military Order's ) and Tow Packages of any Division.

The 1972-79 727 Tow Package For The Trucks have a OEM Transmission Cooler
in front of the Radiatior. The same Tow Package Truck will have a Clutch Fan
Drive with a Seven Paddle Cooling Fan.

You may view it at http://autos.groups.yahoo.com/group/72-79DodgeTrucks/ .



Rodger & Gabby
COS

[soopernaut]

Sorry, the truck and all vehicles I mentioned here were dodge trucks. All the parts were off a Dodge truck and/or a sweptline so I thought this would be the best place. I posted some on slantsix.org and I think I have the info I need. Again, I didn't mean to post a irrelevant thread. I will be more careful next time.

Your thread is not irrelevant. Since sweptline era trucks didn't come with lock-up torque converters the people here most likely haven't dealt with this. Notice Rodger and I are the only ones who responded and neither of us can answer your question.

[PatS]

Rodger, the # on the drivers side is: PK40583311-6507-5904 I know the last 3 numbers are 904 but its not a 904.It has the 727 pan and not the 904. The truck I know for sure was a 1/2 ton longbed. slant six w/auto. It possiby had a towing pkg. It was the original trans. I was told and loked on the vin# and the 6th number was a 8 and I knew it wasn't 68 or 88 . See if this helps.

You have 1 too many digits in the first part of the number so I am using the following PK4058311 (deleting a 3)

So, the number decodes as:

PK= Plant Kokomo

4058311= 1979 D100 Long Extension 225 slant six
also B100, Plymouth Truck, Ramcharger and Trailduster...all 225 slant six
(this does not specifically designate what type of trans it is other than it is either a A-727 OR an A-904. This can be determined by the shape of the pan gasket)

6507= this is the date code using Mopar's 1000 day calendar in which Saturday July 29th, 1961 is Day One. 6507 works out to Tuesday May 22 1979.

5904= sequential build number. The 5904 unit built at the Kokomo plant of that transmission type.

[712edf]

That 10,000 day calender thing, how'd Mopar come up with that? Why not stamp the actual date & be done with it.

Bucky

[PatS]

That 10,000 day calender thing, how'd Mopar come up with that? Why not stamp the actual date & be done with it.

Bucky

Then there would be nothing to decode!!!!

And, the END of that calendar has dire implications for the planet as well. The ending of calendars is catastrophic.

[Rodger]

Bucky

The Calendar usage that we have just learned about used by MoPar is not the only usage of this type.
Other's use the same "type" of manner in showing dates.

Now back to the plug with wires that some are saying is part of the Lock-Up. If you can show
this is true, then follow their direstions. Also notify all others that use or repair the transmission
the printed information stating the Lock-Up Units of the era spoken about are not Mechanically
Operated.



Rodger & Gabby
COS

[Jesuschrystler]

Sorry guys. Just frustrated. I did find a guy who new the trans and it is a lockup. Found the identification and it is a '79 truck trans. It is a lockup according to a trans guy at slantsix.org,( don't ask me why it was in this truck?) I was told by the guys on there that its a electirc switch and hooking a toggle switch to it (with a power source) that it could be manually switched on or off. And if you left it on that when you slowed down it would try and stall the engine. A guy there has his hooked up that way. My truck is at the shop getting seals replaced ( I don't have a lift) so I will try that when I get it back and let you know if it works or....it does nothing....or destroys it! Again, forgive my frustration on my last post....

[OleRed66]

Having a switch would be great, until you have to switch and switch and switch and ...

Try these links, and see if it is possible to do something like this. There should be a way to tap into the fluid pressure, and use a pressure switch to engage and disengage. Think it through and you can get it. You may need/want to do a little extra research. Having a manual switch would be great in that you could actually "interrupt" the signal for the lockup to activate, just in case you need it for whatever reason, towing, hill climbing, etc.

http://www.transmissioncenter.net/SwapInformation.htm

http://board.moparts.org/ubbthreads/sho ... in=4770030

These are for a 727 to a518 swap, but the idea for the pressure switch is there. Good luck.

Edit - Oops, I got to rereading and apparently it is a vacuum switch not a pressure switch that you'll need. Just read and you'll understand, but it should work out!

[garrett]

I would use a pressure switch with a 40 psi rating so anything over 40 mph its locked also anything under 40 mph it unlocks. All you need to do is supply 12 volts to one side of the switch and the other lead to the trans and ground one of the wires from the trans i dont have a schmatic for that set up but im sure it can be found. Use the govenor pressure port for your reading you get 1 psi for every mph then there is no need for running a toggle all the time. Oh ya put a fuse in line also dont need any fires.

[MIKIE-1]

Look at this website. It has info on hooking up a 518. Might have some of the answers yor need to control your lock-up.
700raptor.com.

[mikeys_toy]

I know this thread is old, but after going through this with my 5th ave I have to chime in;
These early lockup trannys are hydraulic, there's no electronics to lock up the converter

[RussRoth]

I know this thread is old, but after going through this with my 5th ave I have to chime in;
These early lockup trannys are hydraulic, there's no electronics to lock up the converter

I have an '01 CTD with an auto and have had a lockup switch on it for several years. The clutch on it is hydraulically locked but electronically controlled. I'm not sure if that relates to your 5th Avenue or not, just thought I would throw that out there for anybody it might be important to.

[mikeys_toy]

later ones were electronic, through the '80s they were mechanical