Torque converter lockup over-ride

[jcolvin]

One of the most useful gizmos you can install in a 4x4 automatic is a torque converter lockup over-ride. This lets you lock the torque converter in whatever gear you have selected, very useful for long hill climbs because it keeps the tranny from heating up and doesn't waste power. On some vehicles it is a very simply mod...simply attach a wire to the torque converter lockup solenoid, attach the wire to a manual switch on the dashboard, attach to 12V and bob's your uncle. You have to remember to turn the switch off before coming to a stop or the engine will stall.

I can't find much info on how TC lockup works on the L400. I assume there's a solenoid but I'm buggered if I can find out where it is....and I did check all the manuals in the L400 download section.

Anybody got any idea where this solenoid is, where the wire attaches to the tranny, or if a manual over-ride is possible?

Jonathan Colvin

[jcolvin]

Bah. After looking some more through the AT manual, it looks like the only electric control going into the tranny is the OD solenoid. That means the TC lockup must be controlled internally through the valve body hydraulic. If I'm right, that's a bummer cause it means you can't install a lockup over-ride switch.

[mrdueck]

It is great mod. I've seen it done on many GM trucks and was hoping one day to do it to the Delica. I'm no tranny expert so I have no suggestions. Just shared disappointment. Fingers crossed that someone my have another idea as to how to address this.
Rudy

[92Nicopolis]

Never say never, you should still be able to do it through the t.p.s since it only controles overdrive it would only work as a high gear lock, but would still come in handy. I think i might try this on my pajaro. it would be nice to pass on the hiway without dropping to 3rd

[92Nicopolis]

looked a little more into it and it has been done befor and works well, i found a rite up on pocuk.com about it, looks pretty easy to do all you need is a screw driver and a little time

[mrdueck]

looked a little more into it and it has been done befor and works well, i found a rite up on pocuk.com about it, looks pretty easy to do all you need is a screw driver and a little time

I just spent 20mins. looking for the right thread. Could you attach the link?
Rudy

[92Nicopolis]

i just spent a while trying to find it again to the search is kinda lame on pocuk, ill look some more after kids go to bed

[92Nicopolis]

Ok i cant find it again, i will keep looking, i do remember that if you adjust the tps so its sending o.96 volts it will not kick down to 3rd unless you go past 3/4 to the floor with the pedal, like i said i will keep looking

[92Nicopolis]

http://www.pocuk.com/forums/viewtopic.p ... hlight=tps
this is not the first one that i was talking about but its almost the same thing

[jcolvin]

Never say never, you should still be able to do it through the t.p.s since it only controles overdrive it would only work as a high gear lock, but would still come in handy. I think i might try this on my pajaro. it would be nice to pass on the hiway without dropping to 3rd

This doesn't sound right, AFAIK the TPS controls shift points (ie 1>2, 2>3, 3>4, and does not control the overdrive TC lockup). Overdrive (torque converter lockup) will only come on in 4th gear. AFAIK all the OD off switch does is stop you from going into 4th gear, so naturally TC lockup will not occur. But this won't help you get TC lockup in 1st, 2nd and 3rd, which is what we want.

[92Nicopolis]

as i said it only works on od not 1st to 3rd, there are a lot more posts on it but no it wont help with the low gears, as i have not done this yet i cant say that i know it works 100% but with the other people that have done it i dont seee how it couldnt I know what your saying but im gona try it and see (its only time in this case) and i have lots of it to spare

[pajerry]

Hey Nicopolis, have you looked any further into this? This one I'll be following for sure!

[92Nicopolis]

i have looked into it and i found that it will not help with locking in a gear, all it dose is work for your overdrive, but you can adjust the cable and tps to make for smoother shifts. i did that and now it shifts great, you could make the cable tight to make it shift later at a higher rpm, or loose for a lower rpm. hope this helps someone