I just installed my tc lockup switch. I took the connectors off the PCM to make sure I had the correct wire. I did NOT cut the wires. I softened the casing with heat pealed it off and then soldered the wires together. I put a jumper in the fuse box. I put the ground wire under the dash behind the panel under the steering column.
When I push the button it lights up. When pushing the throttle when the tc locks up by the computer The light goes off. When I let off the throttle so it idles the light comes back on. Only the computer controls the lockup now as it did before. Does anyone have any idea what went wrong?
At the same time I added the tc lockup switch I added a DTT voltage regulator for the higher pressure of my new transmission.
If you using the light up switch then thats the problem. I had same thing happened to me. I disconnected power wire to it and used only ground wires. That made it work
I ran mine from the correct wire to a switch then straight to ground. Works dandy. I accidently hooked up to the wrong wire and it lit up the wait to start light.
I knew I had originally tapped into the correct wire. Yesterday I had taken the connector off the PCM and even took the white cover off the plug to visually verify the correct wire was being used. When I tried to put it back together I discovered I had put the white part on upside down. A quick fix and things were done.
I ran an extra ground straight to the battery. It did nothing to help the problem. I moved the wires on my switch. I had originally set them to one on the top and one on the right side. I now have them on each side terminal avoiding the middle connector completely.
The bad news is I no longer have a LED light. The good news is I have lockup capability in 3rd and 4th gear. I may try to figure out if I can get the LED light working also. I would like it to be on when the tc is locked up manually. For those who might try this it feels odd to lock up the torque converter and only be taching about 1,000 rpm. You will have to think when using this kind of modification.
For those who might try this it feels odd to lock up the torque converter and only be taching about 1,000 rpm. You will have to think when using this kind of modification.
I wouldnt recommend using this at such low rpms. That may be asking for some slipping.
It is cool though using this switch. I'd have soccer moms in their minivans thinking they are gonna slam it at the light on green so they can get in front of me and make a sudden right hand turn.. They were sadly mistaken. It's even more exciting looking in the rear view seeing what they then have to do to make that turn because they were so positive they were gonna smoke this crappy old dodge...
Then there's Jose in his crappy Honda who also learns a thing or two.
Since my low stall converter though, I havent used it much.
You should have 2nd gear lockup in drive.
If you hit the switch from a dead stop it wont lockup in first. upon shifting, it will or should lockup immediately. I did that at least 100 times with my stock converter. I had the tv cable adjusted to it wouldnt slam gears tho.
Last night I went for a 2 or 3 mile long drive just to see if the lockup switch would work. I was not planning on keeping it engaged at that low rpm. I noticed it acted like a dog at that low rpm and would not recommend using it at such low rpms.
I also installed a voltage regulator to make up for higher line pressure in my built transmission at the same time. Due to a bad ground the truck then took off in 2nd or 3rd gear. That was a short lived problem as it was taken care of almost immediately. The same way I do not want to take off in the wrong gear I do not want to drive at 1,000 rpm locked up in 3rd or 4th gear. The only way that might work out would be on flat ground at a constant speed with no load and no added throttle.
I suspect once I get the other transmission installed with its triple billet tc, higher line pressure and extra clutches that slippage will not be an issue. However, this stock transmission is a completely different situation.
The one nice thing I noticed is one locked up you get some engine braking when you let off the throttle. That should cause the tc to last longer before it wears out the lockup clutch as it is not constantly engaging and disengaging.
If you want to use a light then you have to use a double pole switch (4 terminals) otherwise positive juice flows though the lamp filament to the PCM and screws up lockup.
One thing I noticed is the tc does not lockup unless you step on the throttle. When at idle the tc does not lock up even with the switch on. With a factory sloppy tc the tc lockup helps to lockup at somewhere around 42-43 mph (any slower is to low a rpm) instead of the factory lockup at 47mph and unlock at 45mph. The factory did not set lockup far off from where I would have it. 1-3 mph is as much a judgement call as it is a real issue. The big help relates to a hill that sometimes makes 47mph for lockup hard to achieve. Lockup up at 43 or so is a plus there.
I did take off in drive with the tc locked up. I did get 2nd gear lockup. It was a far to low rpm lockup that only lasted a second or 2. I will not use it that way again. I wish I could get lockup in 2nd without using the JB weld mod. I can not get 2nd gear lockup it taking off in 1st or 2nd gear (apparently normal).
One nice thing about this mod is going down hills. With the tc locked up I do not gain much speed going down hill. My only concern is line pressure at idle. I know an exhaust brake is better however just locking up the tc does not really slow me down hard. It acts more as a cop frustrator when they look for speeding at the bottom of a hill.
You don't really want to use lock up switch in any other gear but second and gear shifter set to 2nd, unless you coasting down hill and want to use engine brake. Even then you should select proper gear for the job. Your stock VB cant do 2nd lock up, but your built replacement most likely will have that option. Before you start locking it in second, you should figure out minimum safe speed on your speedometer to use for lock up. Only in gear shifter in 2. Unless you racing you truck at the track.
When I pull my 10K lb trailer, if I have a need to use lock up, I would select OD off, shifter to 2, take off, feel for second shift and when Im at about 20-25mph I will flip the switch and lock it till I get close to 3000 rpm, then turn off the LU, shift to drive, have it automatically lock itself in 3rd, run up to 2500-3000 rpm, then push OD button to go to overdrive and lock itself when she needs to.
I only want to lock manually in 2nd when pulling hills. From all the threads on this subject, I gather you place a switch from ground to the right wire. WHICH IS THE RIGHT WIRE? Where is it?
You need to modify the valve body for manual 2nd gear lockup.
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