valve body upgrades..4EAT

Tuned200 · 08-15-2008, 08:41 AM

anyone done it? I am thinking about it.

IPT Performance Transmissions Torque Converters and Transmission Parts for Ford, GM, Chrysler, and Import vehicles

the $575 option

a6n6d6y · 08-15-2008, 10:07 AM

Quote:

Originally Posted by Tuned200

anyone done it? I am thinking about it.

IPT Performance Transmissions Torque Converters and Transmission Parts for Ford, GM, Chrysler, and Import vehicles

the $575 option

don't bother on a 04' + FXT with a 'direct control' transmission, all there is to do is put a $2 resistor in there to raise the line pressure

the TCU is located under dash left of steering column

put a (6 Ohm 10 W IIRC) resistor between (B55) No.3 and (B55) No.4 will improve the shift firmness..if it dosent try a 5 or 4 Ohm, don't bother with a VB mod on this vehical..sorry IPT

SkateandDestroy · 08-15-2008, 07:08 PM

are all the Xt 4eat's direct control or just certain years? Thats what makes the IPT valve body mod. not as effective correct?

Can anyone explain exactly what "direct control" implies?

a6n6d6y · 08-15-2008, 10:40 PM

Quote:

Originally Posted by SkateandDestroy

are all the Xt 4eat's direct control or just certain years? Thats what makes the IPT valve body mod. not as effective correct?

Can anyone explain exactly what "direct control" implies?

AFAIK they all are direct control...yes, the direct control is the cause of VB mods being ineffective (non existent)

simply put, it puts the TCU in direct control of the clutches and brakes..in the older system the TCU just controlled when and how firm, but valves and accumulators did the actuation of the clutches and brakes in the transmission

pleiad7 · 08-16-2008, 08:27 AM

Quote:

Originally Posted by SkateandDestroy

are all the Xt 4eat's direct control or just certain years? Thats what makes the IPT valve body mod. not as effective correct?

Can anyone explain exactly what "direct control" implies?

Yes, the direct control 4EAT was introduced with the 04 XT. There's a good description of the direct control system in the tech document for the 04 XT here: Subaru of Australia Technical Documents MY03-04

Quote:

The Forester XT is the first vehicle in the
Subaru range to feature the new ‘Direct
Control’ four-speed automatic transmission.
The gear train of this transmission is the same
as previous models but it now features more
direct electronic control. Conventional
automatic transmission hydraulic control is
called ‘sequence control’ and this system
uses hydraulic switching valves to direct oil
pressure to hydraulic clutches from the oil
pump. This system in order to prevent shift
shock due to sudden engagement/dis-engagement of the clutches, uses additional devices such as line pressure control
solenoids, accumulators and hydraulic control valves. Since this system requires many mechanical components with a large
number of movement combinations it is very difficult to guarantee smooth shifting under all operating conditions.
Additionally if, due to a sudden change in operating conditions, a second gear change is required while the initial shift is in
progress, the second shift cannot be commenced until the accumulator and or clutch operation has been completed. This
can result in sluggish unresponsive gearshift operation under certain operating conditions. The new ‘Direct Control’ system
uses direct computer controlled duty solenoid valves for each hydraulic clutch to simplify the clutch control operation,
providing a faster and greater range of control. The result is improved accuracy and smoother gearshift control with
simplified construction of the control valve assembly.

FXTINTX · 08-16-2008, 09:05 AM

so, this will work on 2004 FXT 4Eat, Correct?

Thanks
RYNO

Quote:

Originally Posted by a6n6d6y

don't bother all there is to do is put a $2 resistor in there to raise the line pressure

the TCU is located under dash left of steering column

put a (6 Ohm 10 W IIRC) resistor between (B55) No.3 and (B55) No.4 will improve the shift firmness..if it dosent try a 5 or 4 Ohm, don't bother with a VB mod on this vehical..sorry IPT

a6n6d6y · 08-16-2008, 09:08 AM

Quote:

Originally Posted by pleiad7

Yes, the direct control 4EAT was introduced with the 04 XT. There's a good description of the direct control system in the tech document for the 04 XT here: Subaru of Australia Technical Documents MY03-04

even with all that thought put into the transmissions control system, it's still a 'unresponsive slow turd' during some driving situations....

my wife's 92 legacy does a better job of being in the right gear at the right time

a6n6d6y · 08-16-2008, 09:15 AM

Quote:

Originally Posted by FXTINTX

so, this will work on 2004 FXT 4Eat, Correct?

Thanks
RYNO

you might want to be careful to make sure the wiring is the same...but yes this will work on all 'direct control' fozzys

if the plugs on the TCU look exatly the same then it should work fine as is

for $35 you can download the service manuals for your car from here..Subaru Technical Information System - Home

you want the resister to jump across the two wires for the "Line pressure linear solenoid"

pleiad7 · 08-16-2008, 11:43 AM

Quote:

Originally Posted by a6n6d6y

even with all that thought put into the transmissions control system, it's still a 'unresponsive slow turd' during some driving situations....

my wife's 92 legacy does a better job of being in the right gear at the right time

I agree... it's sluggish and indecisive at times. If it weren't for the gear selector I would've tired of it a long time ago.

Even the failure-prone SVX transmission has a better feel to it and quicker response to throttle input, and we've been trying for a while now to kill the 4EAT in our 98 Forester to replace it with the JDM STI 4EAT we have in storage. It just won't die.

SkateandDestroy · 08-16-2008, 01:25 PM

Quote:

Originally Posted by a6n6d6y

you might want to be careful to make sure the wiring is the same...but yes this will work on all 'direct control' fozzys

if the plugs on the TCU look exatly the same then it should work fine as is

for $35 you can download the service manuals for your car from here..Subaru Technical Information System - Home

you want the resister to jump across the two wires for the "Line pressure linear solenoid"

Thanks for the info, I might do this..
Are you running this on your XT right now, in addition to the IPT valve body upgrade? Chance of any TCU Codes popping up with the resistor mod?

a6n6d6y · 08-16-2008, 02:19 PM

Quote:

Originally Posted by SkateandDestroy

Thanks for the info, I might do this..
Are you running this on your XT right now, in addition to the IPT valve body upgrade? Chance of any TCU Codes popping up with the resistor mod?

I had an IPT VB, but after trans a failure I opened it to see what they had done to it and to see how much 'metal' was in it...I could find no machining marks and it not look like any thing else was changed..so I put my original (untouched) VB in and just transfered the resister IPT had put on their modded one...and found that it behaved the same..so $600 for a resister to improve the shifting (marginally) I feel a somewhat jipped

I see no reason why putting the resister next to the TCU would work any differently than on the VB, but no I haven't tried this method

if you get a code from this try a resister with a higher Ohm number

SkateandDestroy · 08-17-2008, 06:19 PM

Someone be the guinea pig for this and let me know how it works!!!!!!!!

I'm almost positive the wiring is different for early XT's though..Someone else did a CenterDiff Lock on an 04XT and the pin/plug were different than the 06 model. So I'd imagine the Line Presure would be different too.

Tuned200 · 08-19-2008, 12:54 PM

Anyone have any more input as to if all years are the same?

guroove · 08-19-2008, 01:00 PM

Quote:

Originally Posted by pleiad7

I agree... it's sluggish and indecisive at times. If it weren't for the gear selector I would've tired of it a long time ago.

Even the failure-prone SVX transmission has a better feel to it and quicker response to throttle input, and we've been trying for a while now to kill the 4EAT in our 98 Forester to replace it with the JDM STI 4EAT we have in storage. It just won't die.

What the heck is a JDM STI 4EAT and how do I get one?

Tuned200 · 08-19-2008, 01:20 PM

Quote:

Originally Posted by guroove

What the heck is a JDM STI 4EAT and how do I get one?

x2. Heck I just want to turn the power up to sti levels without killing the 4eat.

08-15-2008, 08:41 AM	#1 (permalink)
Tuned200 Join Date: Jan 2008 Location: Florence, KY Posts: 3,554 Gallery: 0 iTrader: 10 / 100%	valve body upgrades..4EAT anyone done it? I am thinking about it. IPT Performance Transmissions Torque Converters and Transmission Parts for Ford, GM, Chrysler, and Import vehicles the $575 option

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08-15-2008, 07:08 PM	#3 (permalink)
SkateandDestroy Join Date: Dec 2006 Location: New Jersey Posts: 409 Gallery: 0 iTrader: 0 / 0%	are all the Xt 4eat's direct control or just certain years? Thats what makes the IPT valve body mod. not as effective correct? Can anyone explain exactly what "direct control" implies?

08-17-2008, 06:19 PM	#12 (permalink)
SkateandDestroy Join Date: Dec 2006 Location: New Jersey Posts: 409 Gallery: 0 iTrader: 0 / 0%	Someone be the guinea pig for this and let me know how it works!!!!!!!! I'm almost positive the wiring is different for early XT's though..Someone else did a CenterDiff Lock on an 04XT and the pin/plug were different than the 06 model. So I'd imagine the Line Presure would be different too.

08-19-2008, 12:54 PM	#13 (permalink)
Tuned200 Join Date: Jan 2008 Location: Florence, KY Posts: 3,554 Gallery: 0 iTrader: 10 / 100%	Anyone have any more input as to if all years are the same?