Torque Converter lockup switch

[BroncoMarc]

I've been looking over the instructions at the TST site to make a switch to manually lock up the torque converter.

http://www.tstproducts.com/tranny_install.html



I'm kind of curious how this works. What does removing the relay and replacing it with the jumper do, and what does grounding the wire on the connector do?



When the switch is off will the torque converter still lock up on it's own, or does this convert it to a completely manual setup?



The instructions don't really say which pins on the relay to jumper. It's on the diagram, but the pins on my relay aren't layed out like that. Which one's do I jumper? I'm assuming I need to just tap into the B11 line with the switch, and not actually disconnect it, right?



- Marc Reiter

http://www.broncomarc.com/ram/

 

[Joe G.]

Marc,



There are two ways to wire the switch. If you just ground the wire with single pole single throw switch then you can manually lock it of let the computer take care of locking and unlocking. If you use a single pole double throw with center off switch you wire it so that you can manually lock it, manually force unlock, and let the computer take care of locking and unlocking. With the second method the wire from the computer is cut. The computer end goes to one outside terminal on the switch, the transmission end to the center terminal, and the ground wire to the other outside terminal.



You have to use caution with this switch. If you forget and leave it locked it will kill the engine when you stop. Also you can lug it in a higher gear than you would like if you excellerate with it locked. Both of these conditions are very hard on the TC. If you increase the power of your engine you will want to be able to force the TCC to stay unlocked.



The best way to control the TCC is to use DTT's Smart Controller.



Edit: I forgot to mention that it will not necessarily lock up the TCC when you flip the switch. What that does is activate a solenoid in the transmission. If the hydraulic conditions are correct (have pressure) the TCC will lock. It will NOT lock if you flip the switch and you are at idle throttle. That is, if you are going down hill and flip the switch, you have to excellerate a little to cause it to lock. This can get exciting if you have a heavy trailer behind you and you would like to lock the TCC so your exhaust brake will work.

 

[TxDieselKid]

I'm jsut waiting for the "lock up is bad, don't do it" crowd to show up, don't mind me.



Andrew

 

[Steve Roseman]

Lock up is bad!

Just kidding, want to make the Kid feel better.

Marc, what year truck do you have? I have mine wired like Joe says, but I know the TST site shows for certain years you must use a jumper wire on the relay.

 

[Joe G.]

I think the relay business started in '96 with the introduction of the 47RE transmission. Our 47RH trans do not have the relay.

 

[BroncoMarc]

Re: Lock up is bad!

Originally posted by Steve Roseman

Marc, what year truck do you have? I have mine wired like Joe says, but I know the TST site shows for certain years you must use a jumper wire on the relay.

I guess I should have given that info. . It's a 24v 98. Built 1/98.



- Marc Reiter

http://www.broncomarc.com/ram/

 

[Jim Fulmer]

Andy, I won't be in that crowd I'll just tell you my clutch color on the rebuild... . BLUE it is my fault hammering on it and doing a few lock to lock shifts... thing of the past now.



Jim

 

[D. Showan]

mreiter,

I'm with the others, you need to be very careful about when your in lockup and you should avoid shifting locked to locked.



I may try to wire mine up with the main purpose being to force the converter to unlock and stay in 4th gear. It should be like having another gear between 3rd locked and 4th locked. Now, (For a test) starting at about 1700rpm in 4th locked, I tap the OD button twice to get the TC to unlock temporarily and the tach goes to about 1850-1900 (at full throttle). 3rd locked is about 2300-2400 rpm at the same speed. I'm thinking that 4th unlocked might be just right for some hills. I am a little concerned about the extra heat build up in unlock. I don't know if it will be a problem or not, maybe it would be better to just use 3rd locked and not worry about the higher RPM but I'm after higher MPG. Then again when I put in my 250hp fuel plate I'll probably be able to crest more hills in 4th lockup and won't have to worry about it.



Any thoughts about excessive heat build up in 4th unlocked???

Any opinions about which would be more efficient---???

The two choices--

A. locked in 3rd with less heat build up but at higher rpm

B. unlocked in 4th with more heat build up but a lower rpm



Maybe I should post my questions in the products/accessories forum?

 

[Jim Fulmer]

An unlock switch is all good, I have one (a dimmer switch) in the floor and use it at low RPM when in O/D. The best thing to do is get a smart controller from DTT and be done with it..... it's on my list.



Jim

 

[Dieselnerd]

D. Showan:

I used my unlock switch for the first time towing to Arizona this past winter. I was able to go up every grade that I previously had to shift out of OD. In fact I never had to shift out of OD the entire trip. I also use the unlock to get up to speed with the fifth wheel and then let the TC lock at 55-60 mph as I ease up on the throttle. My trailer weighs slightly over 13,000# most of the time. I monitor my transmission temps at the hot line coming out of the transmission. In lockup it's normally at 150 degrees or less. Unlocked, pulling a long grade it never made it to 200. Your idea is a good one and does work. You don't lose all that speed and momentum that you do when going out of OD.

 

[Dennis Garrett]

I have used the three position switch for about 5 years on my 97. Here's a photo of my switch location.

#ad

 

[Jim Fulmer]

Hum... never thought of putting it there, I hid mine in the ash tray in front of the light, close the door and you don't see it.



Jim

 

[RedRamer]

Dieselnerd

good to know it works well.

What king of transmission mods do you have?

thanks

 

[Dieselnerd]

Goober, Dave Goerend modified my transmission. It has his TC and Valve Body plus he tore down the transmission, inspected all the clutches, updated the front drum seal and set everything up to close tolerances. Works like a charm and a year later I still have to smile whenever I step on the throttle.

 

[RedRamer]

You got the triple or single TC?

 

[Dieselnerd]

Single. Triple was not available last year.