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Re: Power Mode Override Switch - Update
Posted: Fri Mar 30, 2012 7:27 pm
by wtdash
antslegggy wrote:ooooff, thats steep, guess ill keep an eye out for em when im at the scrapper.
did i read that a 93 na tcu would work as well.
?same 4eats right?
As noted, the TCU's are different. You may get weird shifting issues w/the NA TCU on a turbo trans and vice versa.
Turbo 4EAT is different than NA 4EAT See this
POST:
In order to handle the increased torque produced by the turbocharged engine, the 4EAT Transmission uses a larger Torque Converter. For additional strength, the input shaft has also been shotpeened. In both the Forward Clutch assembly and the High Clutch assembly, the number of drive and driven plates has been increased by one (1), while the retaining plate thickness has been reduced. The Low/Reverse Brake assembly has increased the number of plates by two (2), but the thickness has been reduced. The outer diameter of the Servo piston (band application) assembly has been increased in order to provide more band clamping force. Of course, the servo piston seals have also been enlarged to match the servo piston diameter. Due to the new piston shape the number of "O" ring seals has been reduced by one (1) Lubrication passages have been added to the Planetary Carrier assembly for increased gear durability. Finally the logic in the Transmission Control Unit (TCU) has <missing the rest>
Re: Power Mode Override Switch - Update
Posted: Fri Mar 30, 2012 11:04 pm
by ciper
I don't think the differences are big enough to cause shifting issues. They are for improved reliability. Its not exactly the same but I ran a 98 outback transmission with 4.44 final drive off of a 91 legacy TCU.
Re: Power Mode Override Switch - Update
Posted: Mon Dec 03, 2012 10:48 am
by Corifto
I did this today, and it's quite enjoyable, and only took a few minutes of actual work. The rest was finding a place that sold something to de-pin the connector.
And this video helped quite a bit with the method to use to pull the pin correctly.
http://youtu.be/ayxEfRvhLEE
Re: Power Mode Override Switch - Update
Posted: Mon Dec 31, 2012 5:42 am
by xise
I have a spare TCU sitting in my shed if anyone is still looking, not sure what year it came out of though, is there any way to tell?
Re: Power Mode Override Switch - Update
Posted: Wed Jan 02, 2013 7:14 pm
by Legacy777
If you get the part # off the TCU, you can check it against the parts book on my server.
Re:
Posted: Tue Jan 22, 2013 2:13 am
by Yager
ciper wrote:Why not connect the manual mode switch to both the manual mode input on the TCU and the power mode input?
Meaning when the manual mode button was pressed you'd be in both power and manual.
When the shifter is in D manual mode would have no effect but power would be working. I assume that in 2 the car would stay in second and in three the car would stay (mostly) in third.
Does power or manual mode have any effect when the gear selector is in 1?
Has anyone ever tried this? Seems this would work great.
Re: Power Mode Override Switch - Update
Posted: Tue Jan 22, 2013 3:57 am
by Legacy777
Welcome to the BBS.
I don't know if anyone has tried the above, but I wouldn't recommend it because the "manual" mode is not what it sounds like. It is a primitive version of traction control and keeps the transmission from going into 1st gear. It may alter the shift points and AWD mapping slightly, but not enough to really be beneficial.
I would just recommend doing the Power mode if you really want to do anything. I never really used the manual button to "aid" in traction, so it's kind of useless unless you're very gingerly with the throttle.
Most people do think the manual button "holds" the gear longer, which is incorrect. Like I said, I'd just recommend doing the power mode if you want to do the mod.
Re: Power Mode Override Switch - Update
Posted: Tue Jan 22, 2013 5:05 am
by wtdash
xise wrote:I have a spare TCU sitting in my shed if anyone is still looking, not sure what year it came out of though, is there any way to tell?
As stated before in this thread, the Power Mode SWITCH (grounding the pin on the TCU) seems to only work on the '92+ TCU's.
Just for reference - L>R- Legacy TCU- '91 Turbo>'93 Turbo>'90 Non-turbo:
Re: Re:
Posted: Tue Jan 22, 2013 11:54 am
by James614
Yager wrote:ciper wrote:Why not connect the manual mode switch to both the manual mode input on the TCU and the power mode input?
Meaning when the manual mode button was pressed you'd be in both power and manual.
When the shifter is in D manual mode would have no effect but power would be working. I assume that in 2 the car would stay in second and in three the car would stay (mostly) in third.
Does power or manual mode have any effect when the gear selector is in 1?
Has anyone ever tried this? Seems this would work great.
The problem with this, is that the manual mode switch has a different voltage running to it than you need for the power mode switch and it makes things act all funky. Someone has tried it, in this thread I think. But the thread is so long and so old that I'm not looking back through for the post, lol.
Re: Power Mode Override Switch - Update
Posted: Tue Jan 22, 2013 2:58 pm
by Yager
Thanks for the quick answers guys, I will just hook up a seperate switch for power mode.
Re: Power Mode Override Switch - Update
Posted: Wed Jan 23, 2013 3:11 am
by beatersubi
FWIW, I can hold gears manually as long as I need to with 'power mode' engaged. I haven't tried to taking the engine all the way to redline, admittedly.
Re: Power Mode Override Switch - Update
Posted: Wed Jan 23, 2013 7:21 am
by James614
Its been my experience that it will shift about 500 short of red line regardless. Which isn't bad really, since the power peaks there anyways.
My old 93 N/A used to bounce the red line between shifts. Nothing wrong with the trans I could tell. Got rid of it before I could figure that one out.
Re: Power Mode Override Switch - Update
Posted: Sun Sep 15, 2013 7:54 am
by dillonr92
So move said pin to empty slot and run a ground wire from the moved pin to the chassis?
Correct?
Re: Power Mode Override Switch - Update
Posted: Sun Sep 15, 2013 2:41 pm
by wtdash
dillonr92 wrote:So move said pin to empty slot and run a ground wire from the moved pin to the chassis?
Correct?
IIRC, you ADD a wire to the unused Pin 4 slot of 20 Pin TCU connector and ground it. If you move Pin 6 to Pin 4 the MANUAL button no longer works - but that might be OK, since it's rarely used...Plus you don't have to find another wire.
More info
HEREon the USMB.
TD