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Guest Legacy777

Tranny resistor, line pressure, tranny life

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Guest Legacy777

Ok, just thought I should bring this up again, but really explain a little better what this thing is doing.

 

This is what I have found out recently.

 

This little resistor thingy has only been added on the US spec legacies to give soft shifts and crap....what this thing does is reduce line pressure during shifts. Well while it does this, it severely wears the transmission out by reducing line pressure. You can pretty much double the life of your transmission by unplugging this thing.

 

The only thing I have run into as being an adverse affect is that if you physically move the gear selector lever from drive to 3, the transmission will not kick down. So far this has been the only adverse affect I have encountered. I am going to do a little more research as to what this thingy actually is, how it is rigged up, and see if I can bypass it, just run a jumper wire between the connector. Anyone with a new subie, can you try unplugging this thing and see if you get the same results with the transmission not kicking down if you physically move the gear selector lever? I'm not sure if it is my tranny and its age, or just normal operation.

 

Here's a pic of this little POS thingy.

 

trans_connector.jpg

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Guest Legacy777

Hey Mitchell,

 

You wanna take a look on your legacy, see if you have anything like this, you shouldn't....but look around your driver's side strut tower....the front of it. See if there is a wire coming up around there....something similar like mine. I'm really wondering if I can just jump the wires and get my tranny to work when I downshift the lever, but still keep the line pressure up.

 

Thanks

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Guest Scott109

Josh,

 

Don't give up on this one! My 90 is doing the same thing (1-2 shift is firm but the 2-3 shift hesitates before it engages). I'll be watching this thread closely!

 

Thanks,

Scott

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Guest Bagheera85

Yea.. I'll go take a pick, but that area is crowded on mine. :D

 

I'll post the pic on my site, cuz I can never link to a pic and have it work right for some reason.. should be ready in about.. umm.. 10 minutes.. :)

 

Ok.. here..

www.soundillusions.net/si...5/yea.html

 

I'm uploading as I type.. :D

 

Oh yea.. one of my friends, while back in the states, had a s-10 with some shift thingy on it. He could flip a switch, and it would shift HARD, and flip it again, and it'd shift normal.. maybe this is an option for ya? He had the switch(came with the mod) I think mainly cuz his g/f didn't care at ALL for the hard shifts. And they were HARD shifts.

 

And now for the 4th edit.. found what I was talking about. B&M Shiftplus. But on Summit, it only lists it for domestics. But it's only $40.. too bad it doesn't say Subaru.. :)

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Guest Legacy777

alright mitchell,

 

It's in the last of your pics

 

pic3.jpg

 

You see that little aluminum looking thing, looks faded/oxidized. It should be a Jecs device. Can you get the part number off of it. I'd like to compare it to what I have in my car.

 

Anyone with a newer gen legacy, if they would also like to get the part number from theirs so we can compare, that would be very helpful.

 

Thanks.

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Guest subyspeed

hey so ya finally had the shifting problems eh? i'm glad to find out that it wasn't just my car that was doing it. hopefully you find a solution, i like the "hard" shifts but not too keen on 3rd not responding when d/shifting. good luck.

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Guest Legacy777

Well I took the aluminum thing off, and there is a ceramic thing. It measures 12.4 ohms. I am pretty sure that all this thing is, is a resistor. I'm hesitant at the moment to just jumper the thing and basically short the lead together, as I don't want to fry something.

 

I'm still thinkin.....

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Guest meep424

Josh,

 

If it's a resistor, I would NOT run a jumper there. I would, however, be willing to play with different resistances, say 35% higher and 20% lower. If unplugging it makes harder shifts, then I'd start with a resistor with greater value.

 

That is a ceramic unit by the looks of it, made to dissipate a few watts worth of power...say 20 or so? It should have 2 ratings....resistance (in ohms) and a W (watt) rating. If you can find those two, then try a higher value resistor with about the same wattage rating.

 

By trying a few, you might find one that keeps original functionality alive while still hardening the shifts.

 

A good place to order them would either be radio shack online, or digikey.com.

 

Meep

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Guest Scott109

Josh,

 

This morning, right after I read your first post about this, I went out and measured the value of that resistor - 12.7 ohms on mine. I figured that if disconnecting it (infinity ohms) made it shift firmer BUT the power light would flash and you couldn't pull it back into 3rd, then how about somewhere inbetween 12.7 and infinity. I disconnected it and wired a 1K variable resistor in line to replace it. To make a very long story short, the maximum value I achieved without the light flashing was about 900 ohms. I use this car 7 days a week on a rural newspaper delivery route (70 miles and 200 papers a day) so I'll let you know if there's a difference tommorow morning!

 

Scott

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Guest Legacy777

Thanks scott, let us know what you find out.

 

Meep, it does firm up shifts....however it's not really the reason why I want to get rid of it. It's because what it does to the tranny, it reduces line pressure and basically kills the life of the tranny.

 

I took some more pics of the resistor thingy....I'll post in a little bit.

 

Here's pics

 

trannyresistor1.jpg

trannyresistor2.jpg

trannyresistor3.jpg

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Guest Scott109

Okay, here's what I found out. From 12 ohms ( having the thing hooked up) to about 900 ohms, it acted exactly the same - no power light flashes and a slow shift from 2-3. From about 900 ohms to infinity ( having the thing disconnected) it acted the same - the power light flashes 16 times when car is started and a better 2-3 shift.

My experiment shows that adding different resistances in line to replace the thing doesn't seem to effect the tranny - It either sees a connection ( less than 900 ohms) or it sees enough resistance to think it's disconnected ( more than 900 ohms).

I drove for about 45 miles with it disconnected and was always able to pull it back into 3 manually and have it downshift with no hesitation. How long did you guys have to drive with it disconnected before it wouldn't go into 3 when you put it there? Also, how fast are you going when you tried this?

 

Scott

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Guest Legacy777

See here's what I think.....if you have been driving around normally for some time, (ie no ecu reset) and do this mod the computer takes alll that previous time before and averages what little it has with the connector unplugged, and reacts normally. Mine downshifted normally too for a little bit. Then it decided not to.

 

If you're up for it. Reset your ecu, then play with the tranny resistor. If my theory is correct, when disconnected, and an ecu reset, it shouldn't downshift into third.

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Guest Bagheera85

Might want to give B&M a call. For only $40, they Shiftplus kit might be worth it. And there is one for electronic and vacuum controlled trannies, though only list for GM/Ford/Chrysler. Might work with our trannies too. And it's cheaper for you to give them a call than for me, Josh.. :)

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Guest Scott109

See what you can rig up, Josh. I found that any resistance up to a point acted the same way as having the stock resistor hooked up ( I tried a bunch). Any resistance greater than that point ( I tried a bunch) , and the light would flash and it would act like the stock resistor was unhooked. I never found a point where the light wouldn't flash and the shifts were firmed up - it was either all the way one way or the other. Let us know how you make out.

 

Scott

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Guest Legacy777

What about the downshifting thing? When you had a higher resistor in line, did it downshift when you moved the selector from D to 3?

 

That is the ONLY thing I care about. I know having it unplugged defaults it to full line pressure, which is good, and will save wear & tear, heat, and the life of the tranny, I just can't stand it not down shifting when I want it to.

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Guest Bagheera85

Can the ECU 'learn' to forget about it and stop the CEL? Kinda like the impreza hi-flow cats for the newer MY's?

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Guest Scott109

Josh,

Let me put some more miles on it and I'll let you know about the manual downshifts into 3rd.........

 

Scott

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Guest Legacy777

ummmm.....I sorta don't think so. Some times I would get the power light to flash, and other times I wouldn't get the power light.

 

Like I said, I think if you run the car for a while, and then pull the resistor, the computer will average what data it has stored against what it is getting in, and will eventually take that new data as part of it's overall collection of data to base future decisions on........damn we got a thinkin computer...hehe

 

What is this about the Impreza's and the high flow cats? Haven't heard about that........do they meow real loud when you flow it....hahaha :lol:

 

sorry....seriously though....what's up with the cats?

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Guest Scott109

I've been running 3 days and over 300 miles with the factory resistor disconnected. After I start the car I let the power light do its 16 flashes before I pull it into gear. So far its always downshifted into 3 from D when I pull it back manually. I don't do this until the car is going 30mph or less. Maybe that has something to do with it? I figure brakes are cheaper and easier than trannys! Anyways, I'll let you all know if things change but so far, so good.

 

Scott

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Guest Legacy777

Hey, was goin to ask....for those that have tried a larger resistance resistor, what size resistor are you using, how many watts? and all that good stuff.

 

Scott: I'll have to drive around a little more. How many miles is on yours?

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Guest remarcable

I'm not sure I want to do this mod yet.

 

I tend to use 3rd gear quite a bit, usually up to 70mph or so if I'm feeling frisky and am on a fun road. I also drop down from "D" into "3" when my radar detector blips or I pass a speed trap. I know it isn't great for the tranny, but a ticket would be worse for me.

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Guest Legacy777

Marc,

 

Sounds like you drive the same way I do with the D to 3 thing, and the radar detector. I use it too much to not be able to do this. You might try just unplugging it and seeing what it does. You may not get the same problem....worth a shot I think.

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