I have an 87 XT turbo with the computer controlled 4 speed auto tranny. I was wondering if there is a direct bolt in lock up torque converter for better efficiency? As far as i know the torque converters they came with were not lock up and thus not as efficient at higher speeds. If anyone know of one that is a direct bolt in, i'd appreciate it. I also plan to install a magasquirt 2 ECU later, so keep in mind it will have to be compatible with that. Thanks in advance.

Funny you mention the lock up function as I think I was surprised to read somewhere recently that these are a lock up converter. I could be wrong but would not have been reading about anything else.

@Step-a-toeIf you can find the article or whatever said that i would absolutely love to read it.

Edited August 14, 20205 yr by SiriusBlack

That won't happen, I likely read it on the 'net 

it may have been a review in the day ....

I think it does have one.  Why wouldn’t they have a lock up converter?

Many many years ago someone from NZ or Aus said they installed an EJ 4EAT into and XT6 (Same trans) by repinning or swapping harnesses.

If it is a 4EAT it will have a lock up torque converter.

Torque converter lock up is most noticeable when warmed up, in 4th gear above 40 mph. With a steady throttle on a level road you will see an engine RPM drop when it happens. You may or may not "feel" it, because it can happen fast or slow. When in lock up, it you slightly increase the throttle you will not see an RPM increase. When not in lock up, you will see an RPM increase.

From the 4EAT manual.
The 4EAT Transmission is a 4 speed, microprocessor-controlled transmission that was first introduced in 1987.5 Subaru models. It features a lock-up torque converter which locks up in all forward gears except 1st. It has been offered in FWD or Full Time AWD configurations.

Duty Solenoid “B” is located on the lower valve body next to the ATF temperature sensor. It operates the lock-up clutch (inside the torque converter) in 3 modes: “ON,” “OFF,” and a gradual “ON/OFF” control of the lock-up clutch during gear shifting in order to reduce shift shock.

If duty solenoid “B” fails, the torque converter lock-up will not occur.

 

You can find several 4EAT Phase I transmission manuals here. For the connector wiring you need the FSM.

http://jdmfsm.info/Auto/Japan/Subaru/--Articles--/--Transmission--/

 

Edited August 14, 20205 yr by Rampage

Well my XT is an 87 not the 87.5. It has the part time push button 4 wheel drive. Many of the original articles and magazines i found said that all XTs that came to the US from the start of production in 85 have a 4 spd electronically controlled transmission. Ones sold in their home market of japan apparently had the 3 spd. So as far as i can tell mine has a 4spd auto, but since it isnt the half year with full time AWD i have no idea if it has the lock up torque converter.

Your shifter will either have D, 2, 1 or D, 3, 2 with a button for 1 hold.

My '89 XT6 4EAT definitely has lockup. I don't believe the 4EAT was available before '87.5, as the transmission tunnel got bigger specifically for that. I think the 3AT in my old Loyale had lockup, but I was in highschool when it still had an auto.

 

IF it doesn't have it, it would be very hard to retrofit, as it is controlled via a solenoid in the valve body and passages. You'd have to swap out for the EJ transmission, which requires some modification.

Edited August 14, 20205 yr by Numbchux

Look on the top of the bellhousing above the starter for a long sticker with 10 digits starting with TZ******** .

On the other side are there 2 connectors, a 12 pin and 16 pin?

You can also download some of the pdf files from that site and look at the pictures of the tranny.

I have never seen a part time AWD 4EAT. My 85 XT had the 3-speed.  

48 minutes ago, john in KY said:

I have never seen a part time AWD 4EAT. My 85 XT had the 3-speed.  

good catch, I missed that line.

Yep, definitely a 3AT, then.

Have to say I have not heard of our Subarus having a 4 speed auto in just FWD.Obviously I have not read what you have about these !

Count your gears as you go through them manually or slf shift I reckon you will have three forward gears.

The four speed only began with electronic intervention and from memory you would have quite a fat electrical connector going to trans, and transmission in fuse panel?

What gets me is how and when the E4AT name changed to 4EAT ??

I have seen sales brochures in Japanese and the only characters I could make out was E4AT

Well, when I get it running again I plan to count the gears. However I double checked the factory owners manual and it says it has a 4 SPD. However I have a factory service manual for the 86 model year and it says that the 86s at least had 3 SPD. It's just baffling. I'll have to count them when I get it running again.

@Rampage I got that part number off the bell housing, where do I go to decode it into the actual part?

Our 95 Legacy 4EAT originally had TZ102ZAA**.  The 10 is the gear ratio, ours is 4,11.

What number do you have?

@Rampage the number I got off the housing is, TX86K362FC-TW. That's on an automatic with part time on demand push button 4 wheel drive.

Edited August 15, 20205 yr by SiriusBlack

I don't know what the TX is. I have only worked with the TZ 4EAT trannys. I'll have to do some research. Hopefully someone else will know.

I looked up your 87 on Car-Part.com and they show one listing in Gettysburg for an 88 XT Turbo AWD 4 speed auto trans. But, they did not list any numbers.

Edited August 15, 20205 yr by Rampage

Take a look at the chart on this page. Scroll down to the bottom for XT. It shows a TX number like yours, but where you have a "6" they show a "G" and it is a 3 speed.

https://web.archive.org/web/20080801230226/http://prosubaru.com/tech/transid.htm

 

4 hours ago, SiriusBlack said:

Well, when I get it running again I plan to count the gears. However I double checked the factory owners manual and it says it has a 4 SPD. However I have a factory service manual for the 86 model year and it says that the 86s at least had 3 SPD. It's just baffling. I'll have to count them when I get it running again.

Factory manual, what section chapter and page?

I have full 86 manuals and for 87 I have 2,3 and 6

 

What is the 7th letter of your VIN?

And what is the 11th character?