Torque converter lockup switch
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 758
Likes: 14
From: Ville de la Baie Quebec. A winner is just a loser who tried again.
Torque converter lockup switch
Hello
I'm going to install the 200r4 this weekend,, studieing the wiring diagrams from Bowtie it seems rather simple. I thought of purchasing there kits but found them rather expensive for a had full of wires and connectors that I have readily available at home. I do have a couple questions,, maybe someone can help me out here.
http://www.700r4.com/tech/tcc/index.shtml
Keeping this simple
In the brake switch method,, is the 4th gear switch fed hot (12v) at all times to in turn send voltage to the solenoid when in 4th,,, then when brakes are applied the power is cut and lockup canceled.
Any suggestions welcome
I'm going to install the 200r4 this weekend,, studieing the wiring diagrams from Bowtie it seems rather simple. I thought of purchasing there kits but found them rather expensive for a had full of wires and connectors that I have readily available at home. I do have a couple questions,, maybe someone can help me out here.
http://www.700r4.com/tech/tcc/index.shtml
Keeping this simple
In the brake switch method,, is the 4th gear switch fed hot (12v) at all times to in turn send voltage to the solenoid when in 4th,,, then when brakes are applied the power is cut and lockup canceled.
Any suggestions welcome
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Power is on to the brake switch which is closed (brake not applied) then to the 4th gear switch in the trans (normally open) then to the TCC. When it shifts to 4th, the switch closes and the TCC locks. Touch the brake and the brake switch opens kills the power.
Your thoughts are correct. I'd also think about the possiblility of adding a vacuum switch too- that way a slight increase in throttle wll dump the lockup, which adds the torque multiplication of the convertor back in and will hold it in 4th (not locked). May improve the feel a little. As it is in the diagram, as soon as it hits 4th the TCC locks- basically 2 shifts at the same time. Might feel a bump when that happens.
Your thoughts are correct. I'd also think about the possiblility of adding a vacuum switch too- that way a slight increase in throttle wll dump the lockup, which adds the torque multiplication of the convertor back in and will hold it in 4th (not locked). May improve the feel a little. As it is in the diagram, as soon as it hits 4th the TCC locks- basically 2 shifts at the same time. Might feel a bump when that happens.
Safety Car
Joined: Aug 2001
Posts: 3,681
Likes: 200
From: Waterford Mi
Adding a vacuum switch is a good idea. I had some extra cash so I installed a B&M controller instead. Now my convertor locks only if I am going over 40mph.
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 758
Likes: 14
From: Ville de la Baie Quebec. A winner is just a loser who tried again.
Power is on to the brake switch which is closed (brake not applied) then to the 4th gear switch in the trans (normally open) then to the TCC. When it shifts to 4th, the switch closes and the TCC locks. Touch the brake and the brake switch opens kills the power.
Your thoughts are correct. I'd also think about the possiblility of adding a vacuum switch too- that way a slight increase in throttle wll dump the lockup, which adds the torque multiplication of the convertor back in and will hold it in 4th (not locked). May improve the feel a little. As it is in the diagram, as soon as it hits 4th the TCC locks- basically 2 shifts at the same time. Might feel a bump when that happens.
Your thoughts are correct. I'd also think about the possiblility of adding a vacuum switch too- that way a slight increase in throttle wll dump the lockup, which adds the torque multiplication of the convertor back in and will hold it in 4th (not locked). May improve the feel a little. As it is in the diagram, as soon as it hits 4th the TCC locks- basically 2 shifts at the same time. Might feel a bump when that happens.
Safety Car
Joined: Nov 2005
Posts: 3,960
Likes: 573
From: Lompoc, CA. Santa Barbara County
Adding a vacuum switch is a good idea. I had some extra cash so I installed a B&M controller instead. Now my convertor locks only if I am going over 40mph.
Bee Jay
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 758
Likes: 14
From: Ville de la Baie Quebec. A winner is just a loser who tried again.
Wow, you would need some extra cash for that. I have a $5 switch on my console to lock up manually. The brake pedal will still disconnect. I find that I use the lockup very rarely because I'm rarely on the interstate, and even then, when I give it a little gas or a lot of gas, the response with lockup not engaged is much mo betta. At light load highway speeds, the converter isn't slipping that much. The B&M controller is speed activated, I wonder if anyone has used an rpm activated switch. I wouldn't want lockup at anything under 2000 rpm. My previous 700R4 only locked up in 4th.
Bee Jay
Bee Jay
Burning Brakes
Joined: Aug 2007
Posts: 1,173
Likes: 1
From: Liberty Missouri
Wow, you would need some extra cash for that. I have a $5 switch on my console to lock up manually. The brake pedal will still disconnect. I find that I use the lockup very rarely because I'm rarely on the interstate, and even then, when I give it a little gas or a lot of gas, the response with lockup not engaged is much mo betta. At light load highway speeds, the converter isn't slipping that much. The B&M controller is speed activated, I wonder if anyone has used an rpm activated switch. I wouldn't want lockup at anything under 2000 rpm. My previous 700R4 only locked up in 4th.
Bee Jay
Bee Jay
This is something I would like to wire in on my 200r4. Do you have a diagram of how you wired the switch? I think this would solve my problem of lugging at lower speeds. If I am understanding you correctly you wired a switch that keeps the converter from locking in until you manually flip the switch then it operates normally….am I correct???
Safety Car
Joined: Aug 2001
Posts: 3,681
Likes: 200
From: Waterford Mi
I did the $5 toggle switch before I went to the B&M controller. The B&M controller makes it completely hands-free and if wired correctlly iwll lock the convertor in any gear , like 3rd, as long as you are going faster then the setpoint.
Last edited by redwingvette; Apr 22, 2009 at 05:08 PM.
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Safety Car
Joined: Nov 2005
Posts: 3,960
Likes: 573
From: Lompoc, CA. Santa Barbara County
Bee Jay
Burning Brakes
Joined: Aug 2007
Posts: 1,173
Likes: 1
From: Liberty Missouri
Great, thanks for the info guys! So basically you are just breaking the 12V that goes to the tranny. When the switch in the open position no 12V passes through and no lock up on the converter. Correct???
Racer
Joined: Oct 2001
Posts: 420
Likes: 11
From: tuttle ok
When I installed my 200 I used a 4th gear pressure switch in the transmission. So 12 volts goes through a brake switch then to the 4th gear pressure switch and when the tranny shifts into 4th the pressure switch makes and sends 12 volts to the lockup solenoid. If I am slowing down and step on the brakes if the tranny is still in 4th the circuit is broken by the brake switch and the lockup relaxes. With this wiring method the only time the converter is locked up is in 4th gear and no brake applied. If you have your TV cable adjusted correctly this circuit works very well and is simple to wire. If you step on the gas and the tranny down shifts to 3rd or lower the converter automatically unlocks because you have down shifted out of 4th so the pressure switch relaxes and the circut is broken to the lockup solenoid. Clear as mud right?
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
The only problem with having a switch to disable the TCC is if you forget to turn it back on when you hit the highway, the trans may overheat. The TCC hydraulic circuit forces the pressure to the cooler to nearly double.
I suggested the vacuum switch just for a better feel- if you are in 4th, the TCC locked, and you give it a little more gas (like up a hill) the TCC will drop and you'll get the torque multiplication from the convertor to help you over the hill. It's not needed by any means, but it will give you a little help on a hard pull. Without having to get in the gas hard enough to make a 4-3 shift.
I suggested the vacuum switch just for a better feel- if you are in 4th, the TCC locked, and you give it a little more gas (like up a hill) the TCC will drop and you'll get the torque multiplication from the convertor to help you over the hill. It's not needed by any means, but it will give you a little help on a hard pull. Without having to get in the gas hard enough to make a 4-3 shift.
Safety Car
Joined: Nov 2005
Posts: 3,960
Likes: 573
From: Lompoc, CA. Santa Barbara County
The only problem with having a switch to disable the TCC is if you forget to turn it back on when you hit the highway, the trans may overheat. The TCC hydraulic circuit forces the pressure to the cooler to nearly double.
I suggested the vacuum switch just for a better feel- if you are in 4th, the TCC locked, and you give it a little more gas (like up a hill) the TCC will drop and you'll get the torque multiplication from the convertor to help you over the hill. It's not needed by any means, but it will give you a little help on a hard pull. Without having to get in the gas hard enough to make a 4-3 shift.
I suggested the vacuum switch just for a better feel- if you are in 4th, the TCC locked, and you give it a little more gas (like up a hill) the TCC will drop and you'll get the torque multiplication from the convertor to help you over the hill. It's not needed by any means, but it will give you a little help on a hard pull. Without having to get in the gas hard enough to make a 4-3 shift.
Bee Jay
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 758
Likes: 14
From: Ville de la Baie Quebec. A winner is just a loser who tried again.
When I installed my 200 I used a 4th gear pressure switch in the transmission. So 12 volts goes through a brake switch then to the 4th gear pressure switch and when the tranny shifts into 4th the pressure switch makes and sends 12 volts to the lockup solenoid. If I am slowing down and step on the brakes if the tranny is still in 4th the circuit is broken by the brake switch and the lockup relaxes. With this wiring method the only time the converter is locked up is in 4th gear and no brake applied. If you have your TV cable adjusted correctly this circuit works very well and is simple to wire. If you step on the gas and the tranny down shifts to 3rd or lower the converter automatically unlocks because you have down shifted out of 4th so the pressure switch relaxes and the circut is broken to the lockup solenoid. Clear as mud right?
Racer
Joined: Oct 2001
Posts: 420
Likes: 11
From: tuttle ok
If you are running 3:08 gears I think the vaccuum switch is probably a good idea. I am running 3:55 so I rarely if anytime run into a situation where the car is lugging or needs to downshift in normal cruising.
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 758
Likes: 14
From: Ville de la Baie Quebec. A winner is just a loser who tried again.
I will keep this in mind if required,, right now I am with 3.08 gears but have a 3.36 waiting to be install sometime in the following weeks. I haven't reserched any vacuum switch,, I assume they are redilly available from the big tranny vendors,, I'll check it out.
1st Gear
Joined: Aug 2006
Posts: 1
Likes: 0
From: Lakeville Minnesota
In addition to the brake switch I used a Lock It Later switch from TCI that lets me set a time delay when my 4L60 goes into 4th and calls for converter lock up. I am currently using 3.70 gears and I have not needed any other control switches. By adjusting the delay (3 seconds) I am getting an even shift sequence and no jerk into 4th gear. Money well spent, it even comes with a wiring diagram
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Quote:
The vacuum switch sounds like a good idea,, if I understand this correctly, once the lock up is ingaged in forth gear it stays locked unless the brake switch is applied,,ok,,, what happens when the gears drop and no braking is applied ?? Is this where the vacuum switch comes in ?? Also,, does it come into play when kick down is applied ?
04-22-2009 10:38 AM
Anytime the trans drops out of 4th, the 4th switch opens and unlocks the TCC. Same for a detent 4-3 shift. The vacuum switch just holds off the TCC a bit so you don't get a 3-4 shift and a TCC lockup at the same time.
