Engine/Transmission (1998.5 - 2002) Disabling the torque convertor lockup circuit

[Cessna421]

Over the years I have had the torque convertor lock up unlock issue as many of us have. I have been able to correct it for a few years at a time but it always returns. I have tried all of the "voodoo" fixes that are out
there and none of them work as a permanent fix. I never have nor will I ever tow anything with my truck so as a last ditch effort I was wanting to disable the torque convertor lockup circuit. Has anyone done this or
replaced the convertor with a non-lockup unit? Best as I can determine there is on a couple of hundred RPM gain without the lockup and since I don't tow I don't care about the RPM or if the trans runs a little warmer. Opinions???

 

[BD-Hector]

Our BD Touq/unloc kit might be just what you are looking for.

• Prevent the ECM from activating the lock-up clutch when such an action would drag the engine rpm out of the optimum torque range, or, when traveling at such speeds that would cause the ECM to cycle the lock-up clutch in and out.

https://www.dieselperformance.com/s...it-ford-1999-2003-7-3l-dodge-chev-6-5lt-16231

 

[BigPapa]

Yes, I have mine wired to operate manually with a dimmer switch in the floor.

TST has some good instructions here:

http://www.tstproducts.com/Torque Converter Lockup Switch.pdf

They say to tap into the Orange/Black wire, not to cut it, but I cut mine and connected my new wire to the loose end, not the end going to the PCM. It’s been working great for over 100K miles. Occasionally I forget it’s locked up and it will kill the engine if you come to a stop. I am going to wire in a relay to power an LED so I know visually when it’s locked, just haven’t gotten to it yet. It also functions as an anti-theft device since the truck will die when put in drive with it locked.

 

[Monstermaker]

Your problem most likely stems from AC leakage from your alternator. If you're not familiar, google AC ripple testing for your alternator.

For the manual lock switch, you don't need a relay for your "locked" indicator light. Just run +12V to your lamp and use the ground from the switch to turn the light on and off.
If you leave the truck wiring so that the computer can also still lock the converter, the light will come on when the computer calls for lockup too, which is annoying because you won't know if you have your switch on or off.
To easily solve that, grab a diode from your local Radio Shack store and put it inline with the lamp, between the lamp and the wire coming from the computer.
Then the lamp will only respond from current coming from the switch. That's how I did mine.

 

[rotohead]

I too have struggled with the Lock/unlock issue and about two years ago I think I've found the ultimate fix. I've done the noise filters, grounds, replaced generator, rerouting the wires from APPS to PCM, aftermarket APPS and all seemed to fix it initially but would eventually come back. Two years ago I did a simple thing. There is a black ground wire w/brown tracer that runs through the wire bundle that sits right on top of the generator and connects to the passenger side battery. Take that black ground wire out of the bundle as far back to the drivers side as you can, secure it on top of the radiator well away from the generator and around to the passenger battery as you can. No need to cover it in foil or any of that nonsense. Mine has shifted perfectly for the longest period of time since the problem first showed up about 12 years ago. I hope this helps.

 

[MarkMullins]

I too have struggled with the Lock/unlock issue and about two years ago I think I've found the ultimate fix. I've done the noise filters, grounds, replaced generator, rerouting the wires from APPS to PCM, aftermarket APPS and all seemed to fix it initially but would eventually come back. Two years ago I did a simple thing. There is a black ground wire w/brown tracer that runs through the wire bundle that sits right on top of the generator and connects to the passenger side battery. Take that black ground wire out of the bundle as far back to the drivers side as you can, secure it on top of the radiator well away from the generator and around to the passenger battery as you can. No need to cover it in foil or any of that nonsense. Mine has shifted perfectly for the longest period of time since the problem first showed up about 12 years ago. I hope this helps.

dead thread warning..
I hate to have to revive this but I've been doing searches on this subject this morning. My '01 automatic 24 valve has been dong this odd thing where warm or cold when I shift out of park to drive, or shifting into drive from anywhere else it'll kill the engine. I had some hunting issues a few years ago and had the (B-D?)throttle valve pull cylinder installed which seemed to help that issue. This killing the engine thing is dangerous especially if I need to get on it to get out of someone's way pulling out. Does all this have to do with the alternator noiseor could I have some other problem. Could someone point me towards a couple threads that describe the alternator noise fixes? Grounds? Help, I'm kind of stumped here.

Mark M.

 

[cerberusiam]

My '01 automatic 24 valve has been dong this odd thing where warm or cold when I shift out of park to drive, or shifting into drive from anywhere else it'll kill the engine.

Sounds more like the TC has failed.

 

[MarkMullins]

any tests I can do without having to go to the trans shop? this transmission is 4 or 5 years old but doesn't have much mileage. maybe 60,000?
That is guessing high too.

 

[cerberusiam]

How does it feel when you accelerate from a stop? Killing the engine, dragging rpms way down, or causing the engine to start revving when placed in gear is a typical TC failure. You should also feel a noticeable lack of power and throttle response when under about 35 mph or so. Once you get up to speed it feels and drives fine.

There is no "test" other than feel and symptoms for a failed TC like what I think you are describing, just experience and a SWAG.

 

[MarkMullins]

Well, I have felt it start out in 2nd gear a few times but not very often. Power off takeoff is fine, it hasn't done that at all. it's never killed the engine when coming to a stop either.

 

[cerberusiam]

Does it pull the idle down at all when stopping in gear? How about shifting into reverse, does it pull the engine down or kill it?

 

[MarkMullins]

No idle pull down, but like in parking lots when going between park to drive it'll pretty often kill the truck. It's been doing that a long time (couple years)but hasn't seemed to get any more frequent. I haven't bothered to fix it until now because I have just altered my habits a bit to compensate for it so I've not felt unsafe. At this point, I am just annoyed enough to address it.

 

[cerberusiam]

Do you have a low stall TC or stock? I assume no codes showing on a scanner? It isn't unusual the TC failing will be intermittent, but, not for years as a rule. It is just as likely there is an issue in the VP-44 that isn't showing codes. The symptoms you describe are definitely not the norm or even consistent with typical issues.

 

[MarkMullins]

It's a stock trans and converter. My vp-44 was replaced 3 or 4 so years ago along with a fass platinum addition at that time. I'm really hoping to not have to replace any major assemblies for awhile.

 

[MarkMullins]

oh and I haven't had the trans on a scanner with that capability..might ought to get the thing into a good shop. I'm not sure I now trust the shop who did the transmission replacement either. I had it to them when it was "hunting" or I guess it may have been locking and unlocking, not sure. it felt as if the truck was coming in and out of gear but I was told at the time that the hydraulic pressure was too low. What the hell man.. can't you buy a product that's been assembled correctly anymore??