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Torque Lock-up switch

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Old Nov 9, 2005 | 06:34 PM
  #1  
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Torque Lock-up switch

Received my electric exhaust brake kit and installed it today. Got it off Ebay for $95 and it was fairly simple to install. But they also sent me a wire harness i could use for a torque converter lock-up switch. Has anyone every used one of these? The instructions say under no circumstances should you ever switch it into operation at idle, when stopped, or below 20 mph. Also DO NOT engage until traveling 45 mph. Are these safe to use and can they be used while the exhause brake is on?
 
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Old Nov 9, 2005 | 06:47 PM
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yes, the TC lock-up is basically a necessity when you have an automatic transmission, when using an exhaust brake. if the transmission is digengaged (freewheeling, usually below 30 mph) the exhaust brake is pointless, basically only slowing down the engine and doing nothing for ground speed. Black Cloud Diesel has a TC lock up switch on their site, i am thinking of one. i like how the Torqshift can downshift to hold the truck back in ALL GEARS when on Tow-haul.

that is the end of my knowledge on this, and i too have a question for the guys out there-
when in TC lockup mode, will the transmission downshift to a lower gear and will the TC still be engaged, on other words will it act like a TorqShift in tow-haul? i hate pulling up to a stop, and once i get below the 39-40mph mark, the engine just idles and it is "all brakes" slowing me down. that is worth the money itself
 
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Old Nov 9, 2005 | 06:58 PM
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You cant use the TC lock up at speeds below 25.And on my truck the TC lets go at 25,so whats the sence of me installing a TC lock up.If i what to slow down more i just take it out of over drive.Works good so far.
 
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Old Nov 9, 2005 | 08:18 PM
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RAMPAGE_F350
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From: Central Alabama
Dewman-yes,used properly the T/C lockup is beneficial.Used in combination with the EBPV brake going down steep declines pulling a heavy load, you don't have to use your brakes as much or at all to maintain a constant speed.
Strokin-yes, with the T/C switch on lockup the tranny will downshift normally just make sure that you switch it off before coming to a stop other wise your mule will stall(its like having a clutch)
Blueeyes-the T/C can be switched any time above 2000rpm safely,like when you start from a dead stop going up a steep incline this reduces slipping and lowers tranny temps.
Also when I lock mine it locks pretty hard, it may vary from truck to truck. One more thing don't try to put your mule in gear with the T/C locked up, you wont like what you hear! Don't get me wrong it is a great Mod but use it wisely.
 
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Old Nov 10, 2005 | 04:26 AM
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Originally Posted by RAMPAGE_F350
Blueeyes-the T/C can be switched any time above 2000rpm safely,like when you start from a dead stop going up a steep incline this reduces slipping and lowers tranny temps.
Also when I lock mine it locks pretty hard, it may vary from truck to truck. One more thing don't try to put your mule in gear with the T/C locked up, you wont like what you hear! Don't get me wrong it is a great Mod but use it wisely.


Well I guess that it wouldnt work for me as the truch rarely gets over 2000 rpms,just on the highway.My truck does not down shift,it stays in gear untill i reach about 25 mph,when the TC lets go.
 
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Old Nov 10, 2005 | 04:58 AM
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You can use a T/C lockup down to 1200 rpm. Below that is where the pump pressures get too low. Not only does it work when slowing down, it also works well while cruising. Get up to speed while towing, flip on the T/C lock, set the cruise control, and off you go. If you come to a rise where it wants to unlock and/or downshift, it just throttles right on through it. Coming up a big hill, you can get it locked (I let the PCM lock the T/C and then throw the switch to keep it locked) and it will pull right on up it with little effort and low transmission temps. These are the only times I use mine.
Joe
 
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Old Nov 10, 2005 | 07:48 AM
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How does the torque lockup differ from what the new trucks have (toll and haul mode)? also, on my elec exhaust brake, can i just leave the switch on all the time?
 
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Old Nov 10, 2005 | 08:15 AM
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i would leave the switch on when towing. i guess your harness automatically disengages the brake when on the pedal and when idling (or off the pedal, without touching the brakes) and as soon as you tap the brakes, it will take 2-3 seconds for the brake to come on. i guess it would kick off at idle or somewhere close. i would like to have a seperate switch for TC lockup and another for brake, so i can switch the brake on in the mornings for warm-up.
 
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Old Nov 10, 2005 | 09:19 AM
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Strokin, this kit has a switch for both the TC lockup and the exhaust brake. Apparently when you give it fuel the pressure overcomes the valve and opens it. Let off it and the valve closes. I understand the biggest flaw in the ford transmission is if it ever gets over heated. We got to flagstaff in AZ its a long hard climb. Are you saying if i switch the torque lockup on the transmission will run cooler and pull better?
 
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