Manual Lock-Up Torque Converter

[Maverick Junior Member Find all posts View Profile Close Maverick]

Many years ago, I drove a turbo diesel (2.8 lt 6 cyl) GQ auto Patrol. I was surprised to see it had a manually operated lock-up torque converter button on the dash. It was labeled HOLD. When you pressed this button, it locked the auto into whatever gear it was in at the time.

During a test drive that included some steepish hills, it drove the Patrol up the same hill with the auto "free" and "locked". With the auto able to change gears, i went up this hill doing about 95 kph and with the auto locked into 4th, it went up the hill at just under 90 kph.

I was wondering if its possible to have a similar button installed on the Prado's auto. Where I live, there are plenty of hills on the main highway and my auto is always dropping back a gear, when it could easily go up it in top gear, if only I could manually lock-up the torque converter.

[embi Senior Member Find all posts View Profile Close embi]

Are you talking up through the Pentlands?? or on the way to Ballarat?

[Maverick Junior Member Find all posts View Profile Close Maverick]

Yeah around that area.

[Maverick Junior Member Find all posts View Profile Close Maverick]

Re: Manual Lock-Up Torque Converter

Hi guys,

I was just wondering if any of your electically minded people have found a way to manually lock-up the torque convertor on the Prado?

Mark

[MickL Addicted PP Member Find all posts View Profile Close MickL]

Re: Manual Lock-Up Torque Converter

I was surprised to see it had a manually operated lock-up torque converter button on the dash. It was labeled HOLD. When you pressed this button, it locked the auto into whatever gear it was in at the time.

There seems to be some confusion here as to what a torque converter does.

A torque converter is a fluid coupling that is used to transfer rotating power from the engine to the gearbox, like a clutch in a manual, it allows load(gearbox/drivetrain) to be separated from the power source(the engine)

Losses within the torque converter reduce efficiency and generate waste heat, this is avoided by use of a lock-up clutch that physically links the internals of the converter together, effectively changing the converter into a purely mechanical coupling. The result is no slippage, and virtually no power loss.

The "HOLD" button you discribe is a shift lock for the transmission only. In simply stops the trans from changing gear.

Mick

[damonat Advanced Member Find all posts View Profile Close damonat]

does anyone have the wiring diagram for the lock-up torque converter kit yet.
i'm after it for the 1KZ.
the V6 diagram is on way.
going to make my own wiring etc, just need to know where to wiring onto.

[redland4wd Lurker Find all posts View Profile Close redland4wd]

I found this while looking for something else may be worty giving these guys a try. click the link and scroll down a bit there is a question on this very subject.

http://www.automatictransmission.com.au/askorto.asp

[SteveMc Junior Member Find all posts View Profile Close SteveMc]

Trying to get the Wholesale Automatic Transmission switch fitted at the moment, but the diagram of the ECU they supplied
does not mach up to the 2005 1KZ 4 spd auto! and they dont seem to have any answers either
" think the auto sparky is going to cost a small fortune "

[damonat Advanced Member Find all posts View Profile Close damonat]

Trying to get the Wholesale Automatic Transmission switch fitted at the moment, but the diagram of the ECU they supplied
does not mach up to the 2005 1KZ 4 spd auto! and they dont seem to have any answers either
" think the auto sparky is going to cost a small fortune "

i would be keen to know how you go.
i have Matts kit here, and have copied his kit.
now trying to work out the wire i need to find

[lankx Lurker Find all posts View Profile Close lankx]

Hi SteveMc
I have the same year and model and am considering purchasing the valve body upgrade and torque converter lock-up switch as well, be interested to know how you went getting it fitted,

[Rusty62 Advanced Member Find all posts View Profile Close Rusty62]

Wonder if anyone has thought of a lockup that engages and stays engaged after the ecu tells it and disengages when the brakes are used. A manual lockup push button for engine braking.
This would be easy if i could find the wiring diagram for the torque converter and splicing into the harness. Simple relay, 2 position switch for on, off and a push to lock button.

If anyone has the circuit i can build a kit.

Rusty.

[gxl_d4d Advanced Member Find all posts View Profile Close gxl_d4d]

One thing to consider using relays to hold the solenoid in position would be whether the solenoid is rated for 100% duty cycle. I played around with something similar in my soarer a few years ago. I ended up burning out the lockup solenoid as it was designed to be given a 12V to make it move then 9-10 volts to hold it in place. The solenoid wasn't rated to see 12V continuous.

[SteveMc Junior Member Find all posts View Profile Close SteveMc]

Picked the car up from the sparky today, one very big bill, thiers been about ten ours of research
to find the wright wire & pin out, going to have a chat with the supplier!
The switch does what its supposed to,i would say you will need the valve body replacment if
your looking at the engine breaking side of things, gets a bit rough at low revs.
If you were to modify the relay you could use a 2 position switch to also turn the power off &
get on overdrive effect.

Cheers steve

[SteveMc Junior Member Find all posts View Profile Close SteveMc]

I got the sparky to rewire the relay to turn the torque converter off,
my reason for going this way was over steep hills towing the van the car would
bog down then lose to much momentum drop down a gear and not recover so by switching
off the torque converter i can keep the momentum up, which worked a treat over some steep
hills down south over the weekend.

Sparky has told me for my car the wire is located in plug c, pin 4. Pink with blue trace hope that helps anyone

Cheers Steve

[Rusty62 Advanced Member Find all posts View Profile Close Rusty62]

Sparky has told me for my car the wire is located in plug c, pin 4. Pink with blue trace hope that helps anyone

Cheers Steve

Any chance of a photo of the plug and it's location?

Thanks
Rusty.