Page 1 of 1

can I make the 4EAT "tougher"

Posted: Wed Sep 06, 2006 4:15 am
by snowman
I thought I would make my first thread on this board a practical one...

Just got a 92 Legacy with 166k on it and it's got the 4EAT tranny. Before I bought the car, I had planned a 5MT swap, but after driving the car, I decided to keep the automatic (3500 RPM at 90mph is very nice).

I'm not planning on any real engine mods, but I would like to do what I can to make the tranny hold up through any abuse I can dish out by towing with the car or four-bying over rough stuff.

The tranny fluid looks pretty good, but I'm going to change it and clean out the mesh screen filter, and I'm going to replace the in-line filter in the tranny cooler hose.

Is anybody here running an auxilliary transmission cooler? If so, how big and how have your results been?

Is there anything else I can do to help my transmission stand up to hard use that won't cost a fortune? Any driving tips for a guy that's used to manual transmissions (this is my first automatic car).

Thanks for your help!

Posted: Wed Sep 06, 2006 4:46 am
by entirelyturbo
An auxiliary transmission cooler will do nothing but good. It is true, the number 1 enemy of automatic transmissions is heat. A cool autotranny is a happy autotranny.

I think there's a way to install a transistor or something to make the transmission shift a little faster. Hopefully someone with more experience with 4EATs will chime in on that one. Your shifts will be a little rougher, but I believe it will be a little easier on the clutch packs in your transmission.

Posted: Tue Sep 12, 2006 3:34 pm
by Redlined
Bump to this.

im also interested in "tweaking" my 4EAT.

Any (and all) tips hint and suggestions happily accepted!

Posted: Tue Sep 12, 2006 3:42 pm
by free5ty1e
You mean... there's a way to make my 4eat behave like it's got 4 gears and not a cone with a positionable belt? And it's an electronic solution?

Someone please 'splain, if it's just a transistor I can make that happen and do a write-up... what kinda transistor, where do it go, and what signal do it alter? :)

Posted: Tue Sep 12, 2006 4:37 pm
by Subtle
My 4eat is "built" with amongst other things includes a higher line pressure on the shifts.

At WOT this is good :-D . But at slight throttle, the shifts go "thunk" :(

Is there simple switch instal that would drop the line pressure when aggressive shifting is not required?

By the way, I've detested automatics until this one. Ample torque makes it a lot of fun.

Posted: Tue Sep 12, 2006 4:46 pm
by free5ty1e
<--- detests autotragics, always have, always will.... but am stuck with one for now.

What did you do to increase the line pressure, was this an electronic mod or a mechanical mod?

Posted: Sat Sep 23, 2006 7:32 pm
by Redlined
bump bump

anyone have any word on this?

Posted: Sat Sep 23, 2006 9:23 pm
by Subtle
They put in different solenoids. www.ipttrans.com

Shifts are quick and solid. :D

Posted: Sat Sep 23, 2006 10:02 pm
by free5ty1e
http://www.importperformancetrans.com/subaruauto.shtml

Jeebus... the cheapest thing I see on that page is like $275!! For a solenoid?!? I'm not THAT interested in my 4EAT...

Anyone have technical info on how this works? Is there just a pulse width I need to alter to control the shift engagement harshness?

Posted: Sun Oct 01, 2006 5:56 am
by asc_up
this may sound stupid and it's only because i know absolutely nothing about transmissions and i understand if you make fun of me.....


....but...can you by a lighter flywheel or is that only on mt?

lol

Posted: Sun Oct 01, 2006 6:43 am
by Redlined
You can only put a lighter flywheel in a manual transmition. In an automatic, the Flywheel and clutch assembly are replaced by a "Torqe converter" wich is, essentially, a BIG viscous coupling.

Posted: Sun Oct 01, 2006 6:07 pm
by asc_up
haha ok. i know what the torque converter looks like.

are there any aftermarket things i could do to it to make it lighter or anything?

Posted: Sun Oct 01, 2006 7:50 pm
by Manarius
snowman wrote:can I make the 4EAT "tougher"
Steps:
Jack up car
Remove 4EAT
Insert Dogbox
Lower car

Done.

4eat improvement

Posted: Wed Oct 11, 2006 3:12 am
by head2wind
from what I have discovered the 4eat is not much different than any other auto out there. they do have inherent problems that are related to over heating, under lubrication and soft shifting. the basic rule of ATs apply here with this transmission but is also complicated by the "e" part, meaning the transmission control unit. most of what people want to accomplish can be done with the "transgo" shift improvement kit, improved cooling with a external cooler, and/or a improved selinoid pack.

I have ran across a site that has parts at very reasonable prices. I can't find it now for some reason but I have bought parts from them before so I just need to find the invoice.

However, if rebuilding or improving something like a TH400, C6 or 727 makes you cringe and go "huh?" then the 4eat is WAY out of your league. Take it to someone that can do it with confidence or just completely flush the fluid, put a new filter in, put a additional external cooler on it and call it a day.....

Posted: Fri Oct 20, 2006 7:05 am
by snowman
So I ended up installing an aftermarket tranny cooler and a new inline filter, and I'm going to change the fluid pretty soon (it's still in really good shape). Interestingly, I started out with the extra tranny cooler in series with the stock one, and was getting way too much cooling below 50 degrees. Solution? Went to a hydraulics store and got a diverter valve, so now I can run either just the stock cooler for winter use, or run the stock cooler and the aftermarket one in series for hard driving, towing, or high outside temps.

I'm really not concerned with improving performance, just longevity and reliability. This is my work/travel car, not my racing car. I think the next step is to replace the existing inline filter with a spin-on unit so that I'll actually get around to changing it once every year or so, along with the fluid.

Posted: Fri Oct 20, 2006 4:07 pm
by head2wind
I found my resource again. here is a link to their site and directly to a inline filter solution that they have:
http://www.bulkpart.com/Merchant2/merch ... emperature

Posted: Tue Oct 24, 2006 12:05 am
by snowman
head2wind wrote:I found my resource again. here is a link to their site and directly to a inline filter solution that they have:
http://www.bulkpart.com/Merchant2/merch ... emperature
Dude! That filter kit is awesome! I was having trouble finding one that would fit somewhere near the stock location. I am so getting one of those.

Posted: Tue Oct 24, 2006 5:37 am
by 206er
now dont quote me on this but ive heard that if you unplug the TCU it acts like full manual ie doesnt shift unless you do, no kickdown. I really wish I would have tried this with my ailing 4eat before I swapped.

Posted: Tue Oct 24, 2006 10:27 pm
by head2wind
it will never go into overdrive without the TCU

Posted: Tue Oct 24, 2006 11:58 pm
by Legacy777
There is no overdrive. 4th gear is overdrive.

Seeing that the solenoids are electronically controlled and that the shifter lever is connected to the inhibitor switch which I believe is only electronic, I'd doubt the trans would shift properly, or at all without the TCU.

Posted: Wed Oct 25, 2006 12:21 am
by 206er
well theres only one way to find out, whos going to be our guinea pig!! :twisted: