Jump to content

Auto Trans Wiring for Manual Setup


FullThrottle
 Share

Recommended Posts

Hi All

 

I'm running a RE4R01A transmission connected to the trusty old TD27T and wanted to do a couple of things to it, that I need some advice on:

 

1) Preventing the torque convertor from going into lockup. As this just adds additional load and skips the 3rd gear ratio quite quickly once the trans has warmed up.

 

2) Be able to hold the trans in any gear. (Sort of using it like a manual box)

 

3) Locking the torque converter in any gear to reduce the heat and gain more direct power to the drive-train.

 

I've read through the below post, but the project was never really finished by the member.

 

http://www.offroadexpress.kiwi/Forums/viewtopic.php?f=25&t=34242&hilit=lockup

 

 

Does anyone have a final solution? I was thinking of tapping into each wire on the trans with a portable osciliscope and seeing what voltages are applied for each gear and lockup.

 

Thanks

Link to comment
Share on other sites

G'day mate, you could try this here http://www.nissanpathfinders.net/forum/topic/999-cool-easy-auto-tranny-mod/ I thought about doing something similar to mine and install a switch to cut off the torque converter. Apparently it's a brown coloured wire you should cut just forward of your brake fluid reservoir, cut the brown wire and then put a switch going from that. Not game enough to try it myself though.

Link to comment
Share on other sites

http://s195.photobucket.com/user/kiwi_pete/media/Electrical/Lockupswitchplug_zpsf23764cb.jpg.html

 

This is the brown plug you should look for - apparently cut the blue wire, I think it's just forward of the brake fluid reservoir on the left side of engine bay. Not my fault if you damage your trans.

Link to comment
Share on other sites

So been doing a bit of research and this is possible. The RE4R01A and RE4R03A from Safaris operate the same way so will apply to both.

Caution though: When locking the torque converter in the lower gears, you will have to be careful the bolts don't shear as there is a heap more torque being transferred in the lighter RE4R01A transmission.

 

The transmission operates which a combination of shift solenoids and line pressure. So we will give this a go and see if we can turn an Auto into a manual :-) (Something to do, I'm bored and it's very cheap)

 

 

 

Link to comment
Share on other sites

  • 1 month later...

So my final solution is to use the arduino micro-computer that I've reprogrammed to control the trans in place of the TCU. In addition I'm going with a modified up/down ratchet shifter which will only allow a single gear change per smack of the shifter.

 

Here's how it works.

 

---In Normal Mode---

The TCU is powered on and the standard auto shifter works as normal. Auto operates as per factory. The arduino and ratchet shifter does nothing.

 

---In Manual Mode---

Flick the switch which disables power to the factory TCU and powers up the arduino. Now you can move the factory shifter to D and from there use the ratchet shifter.

 

 

Link to comment
Share on other sites

There is a rail shifter available for these ( :clickdalink:). Arduino sounds like fun, though. If you wanted you could probably ditch the factory TCU altogether and program the Arduino to do its job... alter shift points however you want to for when you want it in auto mode.

 

I saw a vid on Youtube a while back where a guy had three house light switches screwed to the dash of his Chevy. One was TC lockup, the other was solenoid A, the other was solenoid B. He shifted by turning the switches on and off. Seemed to work!

Link to comment
Share on other sites

Neat. Keep posted on how this works out. I've got an arduino 2560 mega board that I've been playing with lately. Really cool devices. I would say it is a good idea to keep the stock tcu as a failsafe though like you plan, since the arduino boards are not industrialized pieces of hardware they will probably not stand up to the abuse and vibrations of life aboard a 4x4 truck. Build a nice dampened enclosure for it though and it should last a while!

 

also my advice is to go through the transmissions harness with an ohmeter to determine the resistive/inductive loads of the solenoids etc so you find out the source current needed to drive them. I don't think the arduino will be able to source enough current to drive the system. You will probably have to build a transistor array and use the arduino just to drive the transistors to saturation and control the logical side of things. Tip31/32 power transistors might work for the job. I believe they will drive 1 amp without heat sinks and generally you want to run a transistor at 50-70% of its rated current throughput.

Edited by Nefarious
Link to comment
Share on other sites

Neat. Keep posted on how this works out. I've got an arduino 2560 mega board that I've been playing with lately. Really cool devices. I would say it is a good idea to keep the stock tcu as a failsafe though like you plan, since the arduino boards are not industrialized pieces of hardware they will probably not stand up to the abuse and vibrations of life aboard a 4x4 truck. Build a nice dampened enclosure for it though and it should last a while!

 

also my advice is to go through the transmissions harness with an ohmeter to determine the resistive/inductive loads of the solenoids etc so you find out the source current needed to drive them. I don't think the arduino will be able to source enough current to drive the system. You will probably have to build a transistor array and use the arduino just to drive the transistors to saturation and control the logical side of things. Tip31/32 power transistors might work for the job. I believe they will drive 1 amp without heat sinks and generally you want to run a transistor at 50-70% of its rated current throughput.

 

Thanks for the advice.

My circuit uses 4 of the digital outputs of the arduino to signal a separate 4 channel relay driver. I'm using relays to control the Solenoids (Shift A and B , TC Lockup and the over-run clutch. This gives me enough power to drive the solenoids while the arduino remains at 5volts in/out.

Once I finalize the complete circuit setup and run it for a bit, I'll post up the specs.

Edited by FullThrottle
  • Like 1
Link to comment
Share on other sites

 

Thanks for the advice.

My circuit uses 4 of the digital outputs of the arduino to signal a separate 4 channel relay driver. I'm using relays to control the Solenoids (Shift A and B , TC Lockup and the over-run clutch. This gives me enough power to drive the solenoids while the arduino remains at 5volts in/out.

Once I finalize the complete circuit setup and run it for a bit, I'll post up the specs.

very nice! Small relays will work just as well as transistors. I'm excited to see your results!

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...