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2nd Gen Transmission FAQ - Maintenance - Differentials - 5MT - 6MT - 4EAT

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It will as long as you change the rear diff with it too. The L and Outback are different gear ratios.....so rear diff and transmission have to be done as a set.


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under construction


The 4EAT is the only automatic transmission available in the BD, BG, and BK Legacys. "EAT" stands for "Electronic Automatic Transmission".


The 4EAT was released in 1988 for use in the Subaru XT6 and Leone Touring Wagon. In 1989 when the EJ engine was released, the bellhousing was changed to accept the newer engine, but for the most part the transmission stayed the same.


The 4EAT has been used in the following Subaru models :

88 - 91 Subaru XT

90 - 04 Subaru Legacy

92 - 97 Subaru SVX

95 - present All Subarus


The 4EAT design has been shared with a few other manufactures as well. Jatco designed the 4EAT, and has allowed Nissan, Ford, and Kia to use the same or very simular designs.



Gear Ratios

1st - 2.785

2nd - 1.545

3rd - 1.000

4th - 0.694

reverse - 2.272


Final drive ratios vary depending on year and model. The majority of final drive ratios are 4.11



Common 4EAT Problems & Solutions

Torque Bind

This is probably the most common 4EAT problem. This is the transmission getting stuck in a 50/50 power split now allowing for slippage in the center diff. Its usually caused by a faulty Duty C solenoid, however can sometimes be cured with a few "drain and fills"


Here is the Part # for the Valve assembly (Duty C) for the BD5 JDM subaru.


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I hope this isnt going to be misplace...but I have heard about a 50/50 mod for the drivetrain. Is this harmful to the car at all? And how do you do it on a second gen. I havent had any luck on the search
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^im assuming you're running a 4eat, imo, the wear on your diff and trans stuff as well as the loss in mpg isnt really worth what you gain, especially when it doesn't actually get you to true 50/50 anyways,


the way the TCU is set up is to distribute power to each end about 60/40 as soon as it detects tire slip..


if you're looking to make the auto more fun to drive, ground a pin on the tcu to change shift points and make it a sportier drive:

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so my 97 leggy sedan with the 4eat is pissing me off a lot. did the sport mode ground mod etc and its just weak, hard shifting from 2-3 (broke 200k mi yesterday)


so on CL is a 4eat from a 03 WRX


is this plug and play?



Edited by purebluedoor
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