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Andyjo

AWD/4WD Impreza, it works! WHOAH! (4EAT = AUTOMATIC TRANSMISSION, not 5spd)

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So many of you may have followed the 12 page long thread in 'new gen subaru', but many of you may have ignored it. So pretty much i installed a switch on the duty solenoid c, cutting signal to it, therefore locking up the clutchpack producing a 50/50 split (front/back). I tested it out after i finnished up and it ROCKS. Circles in a parking lot it was hopping all around and pissed off due to the locked clutch pack.

 

Pavement: (TIGHT Circles in lot)

AWD: Fine, no torque bind issues or anything out of the usual

4WD: One pissed off Subaru, It was hopping and bucking all over the place.

 

Ice/Snow: (Put the front wheels on ice, rear on snow, Floored it)

AWD: Front slipped ALOT before rear powered up to get up on the ice

4WD: Front still slipped, but the rear powered right up onto the ice

 

Ice: (up a 25deg hill covered in ice, following getting onto it)

AWD: front wheels slip before rear (duh...)

4WD: spin both front & back simaltainiously.

 

I'll run some more tests tomorrow, but it seems to be pretty hardcore :grin:

 

Bragging: HA! i Beat Austin & Zap to get a 4x4 Impreza! :-p Just kidding guys, thanks for your insperation! (Zap, is your imp an Auto or Manual?)

 

For the Full story of how i did it check out: http://www.ultimatesubaru.org/forum/showthread.php?t=48865&page=12&pp=10

i threw up some pics for the location of the wires, etc...

 

w00t, i can't wait to play with it more :drunk:

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another thumbs up on this mod. i did it about a year and a half ago and it's been great. another time this really shines is when you pull someone out of mud/snow. the TCU sucks in that situation because it cycles the transfer clutches too much and tends to start rutting instead of pulling and doesn't give you great traction particularly if yo'ure pulling from snow/mud. i always flip that switch before i start moving and yank people right out. i have LSD rear too which is nice with the locking clutch packs. i haven't run into a car/truck i haven't been able to pull out yet.

 

if you're off roading, there is no better mod...and it's so freaking easy. i did it on an XT6 4EAT, so same deal with the older subaru's as well.

 

nice post on the pin numbers, i'll be doing this to my OBS as well.

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Andyjo:

 

Does the behavior differ between the "4WD" setup in "D" and AWD in "1"? Or are they the same?

 

Steve

 

I believe they're different, i really don't think AWD in '1' is a true 50/50 split, because if you try doing circles in a parking lot with it in '1' you don't get that pissed off hopping and bucking that you would with a true mechanical 4WD system. BUT... i'll go try it again :grin:

 

another thing, does anyone know if your 'parking light switch' needs to work to pass inspection? the one on top of the steering column....?

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Mine's a 5 speed. Try this. Put your front tires on concrete and the rears on gravel or something loose. Punch it. Mine will blast off, but the rears will spin some.

 

 

Harsh, didn't know yours was an auto. . .

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Mine's a 5 speed. Try this. Put your front tires on concrete and the rears on gravel or something loose. Punch it. Mine will blast off, but the rears will spin some.

Harsh, didn't know yours was an auto. . .

i wanted to get a 5 speed... but at the time i REALLY needed to get rid of the car i was trading in (so more things didn't break) so i got the auto, there wasn't a 5 speed that i liked there :-\

 

SO i did some more testing and have disproved the claim that in "1" (AWD) there is a 50/50 split, it runs exactly like "D" (AWD) in tight circles on pavement, but if you flip the switch while doing that, in 1, or Drive there's ALOT of resistance, and a little hopping the rear end.

I also tried rock crawling up some steepish ice, first in AWD, very little throttle, just enough to get the wheels turning, it made it up but the front end slipped quite abit as the rear end cought, in 4WD mode it just walked right up, only slipping when all the wheels were on the ice, at this point i gave it a little more nut, and proceeded to spin both the front & rear, it did a sort of wierd shake/vibration at this point, i'm not sure what it was... but it just sort of shook side to side... not moving anywhere

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I've been following that thread too. Way to take initiative and actually do it, instead of just theorizing more and more about it on the computer :banana::banana::banana: Sounds like it works good.

 

I would have, but my car's a manual, with locked 4wd already ('89 GL)

 

The weird vibration you mention when both front are rear were spinning on the ice could have something to do with the auto transmission perhaps? I know that 4wd pickups with automatics (an older dodge dakota in particular) sometimes act weird when going slow through deep sugar-powder snow where you are spinning all the wheels. Where a manual would just happily spin the wheels and eventually get through (or stuck), the automatic starts shuddering sort of like the clutch is juddering, except it doesn't have a clutch. Anyone else know this effect that I'm talking about? I don't know why it might do this.

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HA! i Beat Austin & Zap to get a 4x4 Impreza!

 

 

Oh. And John Mudrat did that to his AT tranny in the Beast for the Subarubicon. He needed it to run the transfer case out of the rear only.

So, it's been done, about 3 and a half years ago. :)

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Oh. And John Mudrat did that to his AT tranny in the Beast for the Subarubicon. He needed it to run the transfer case out of the rear only.

So, it's been done, about 3 and a half years ago. :)

 

 

yeah as grossgary said already in this thread I think... he did this on his xt6 a while ago... haven't heard of anyone doing it on a new gen though

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4x4 moose, you don't need a newer soob, it works on any AWD automatic with a Duty solenoid C, which is all automatic soobs that i'm aware of. probably not the 3AT but who wants to mod that..that might even be FWD only, i don't know much but that's not a common trans anyway. doesn't happen often but XT6.net was ahead of usmb on this one, we've had this mod for awhile.

 

glad to see the EJ nailed down, looking forward to it on my wife's OBS. though i'm scared she doesn't know about cars.

 

john mudrat may have done it but he didn't share or offer advice like Andyjo did! go jo go jo!

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john mudrat may have done it but he didn't share or offer advice like Andyjo did! go jo go jo!

 

hey hey, i respect mudrat with the uppermost respect, i just didnt' know this was possible until that topic came up, i must say, it's been the cheapest modification to this car i've ever done, with the best outcome (well.. the lift was good too)

I hope more people will find the information we came up with useful, and maybe they won't got spend $$ on something that they could do themselves very easily. I always love being the guinea pig for fun things like this, why not right? i've finnished the payments on the car, and i'm going to have it till it dies (i'm hoping for 300k :brow: )

oh well, enjoy! i need to play with it more... mm....

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is this mod for automatics only or can those that have 5spds do it too?

 

no. manuals and auto's are completely different. the 5 speed doesn't have a TCU, clutch pack or Duty Solenoid C...like i said, completely different animals.

 

yours doesn't have a locking center diff? if not, install a 5 speed with a diff lock or push button 4WD option to lock your center diff.

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works on a '91 4eat legacy too, just fininshed mine and tested it... none of that front wheel, then all wheel drive crap, just pure all wheels all the time like my 5mt sedan.

 

Figured it would work cause a '97 4eat out of an impreza bolts up, plugs up and works great on a '90 legacy. So same pin location, #11 on the 16 pin connector, but it's white with black stripe on the car side and black with white stripe on the trans side...

 

This solves the one thing that I really don't like about the 4eat, the front has to slip before the rear kicks in, no more. Thanks for finding the pin# Andyjo, with the rear LSD and the homebrew center diff lock the 4eat does pretty good.

 

Side note adding to what Zapar said, I talked to Mudrat about this a while back when he was mateing the 4eat to the nissan t-case on his beast, he said that a subaru tech told him to cut this same line (pin 11) and it would lock the power output 50/50 so he could drive essentially in RWD, he tried it, didn't work, the beast barely moved (but it did move) I think b/c he had no front axles hooked up. So he opted to force the valve body for Duty Solenoid C to stay open permenantly. Had to pull the trans and pull the valve body off the top of the 4eat, then I believe he removed the ball check valve for duty solenoid c and the 4eat was fulltime 50/50 through the clutches to drive the tcase.

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Side note adding to what Zapar said, I talked to Mudrat about this a while back when he was mateing the 4eat to the nissan t-case on his beast, he said that a subaru tech told him to cut this same line (pin 11) and it would lock the power output 50/50 so he could drive essentially in RWD, he tried it, didn't work, the beast barely moved (but it did move) I think b/c he had no front axles hooked up. So he opted to force the valve body for Duty Solenoid C to stay open permenantly. Had to pull the trans and pull the valve body off the top of the 4eat, then I believe he removed the ball check valve for duty solenoid c and the 4eat was fulltime 50/50 through the clutches to drive the tcase.

 

I took this pic along the side of the trail. :grin:

142johntrannyfix.JPG

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FYI, the 4EAT in 1rst or 2nd worked just fine doing plow duty these last couple of days ...

 

I saw some front wheel spin for a second, but it wasnt bad. I think the 4EAT would be nice with a front LSD.

 

Snow11.jpg

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I believe they're different, i really don't think AWD in '1' is a true 50/50 split, because if you try doing circles in a parking lot with it in '1' you don't get that pissed off hopping and bucking that you would with a true mechanical 4WD system. BUT... i'll go try it again :grin:

 

another thing, does anyone know if your 'parking light switch' needs to work to pass inspection? the one on top of the steering column....?

 

as long as the lights themselves function proporly. most people who don't own subaru's even know that that button exists, let alone what it does.

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really nice FXT somebody has there.... :brow: too bad it is a 4EAT :D

 

HA HAHAHAHA HHAHAHAHAHAHAHA :D

 

that was a good burn! ;)

 

Well, If I still had my 4EAT Impreza, or a 4EAT for that matter, I would be doing this mod. Good info to know regardless though, good work!

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really nice FXT somebody has there.... :brow: too bad it is a 4EAT :D

Honestly, I dont mind that its a 4EAT. Its UNGODLY fast... I'm just sad its not mine, but I did all the convincing to get them to buy it :brow:

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Honestly, I dont mind that its a 4EAT. Its UNGODLY fast... I'm just sad its not mine, but I did all the convincing to get them to buy it :brow:

 

so you get someone to buy it and you get to cruise it on occasion.... sounds win win to me.....;)

 

I almost bought 2 different ones once. Both stick and all I can say is...wow what a test drive... I think my wife still has white knuckles for that drive

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I got 12.9 ohm between pin 11 and 4 on 16pin connector.. pin 11 had brown wire coming from tranny. cut this wire, hooked wire to each cut section, wired to switch.. seemingly no difference. will look more into it after work I was kinda in a beerhaze sunday when we wired it up??

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