Modified Aisin-Warner AW4 Tech

[jeeperjohn]

My little bro ran my jeep out of tranny fluid (and then until it wouldn't move anymore) I pulled it apart and found a broken gear inside the pump. What's the chances of this being the only issue? And I can't find a replacement gear anywhere. Is there a parts store for this gear that I am missing? 125kmiles on jeep.

Start your own thread and post it in OEM tech.

 

[1988JeepXj]

This is a very useful thread, since my question is relevant to AW4 tech and anybody who may undergo a large year span swap, I figured I should post here instead of making a separate thread.

Does anybody know, for sure, if the torque converters ever changed? Something tells me they didn't, but I need to know 100% if I can take a torque converter from an older AW4 and slap in in a newer one. The only reason I would think something changed is if they had to modify it somehow to clear or make room for the input speed sensor.

 

[cal]

This is a very useful thread, since my question is relevant to AW4 tech and anybody who may undergo a large year span swap, I figured I should post here instead of making a separate thread.

Does anybody know, for sure, if the torque converters ever changed? Something tells me they didn't, but I need to know 100% if I can take a torque converter from an older AW4 and slap in in a newer one. The only reason I would think something changed is if they had to modify it somehow to clear or make room for the input speed sensor.

this should probably be a seperate thread..

i have swapped TC's between 87 and 98 rig's.

 

[kastein]

Don't know for sure. The guys at transtar insisted on me giving them the model year of the vehicle when I ordered a rebuilt unit, but I strongly suspect they had no idea and wanted to cover their asses.

Another piece of info - 98 and later units have both input and output speed sensors and the output speed sensor is different from the 97 and earlier output speed sensor. A 98 or later AW4 can be installed in a 97 and earlier XJ by swapping the output speed sensor over and leaving the input speed sensor disconnected, but the reverse is not true. There are 4 distinct "sub-models" of the AW4 I know of:
* 98-01: two speed sensors, 23 spline, 0.75:1 OD
* 91-97: one speed sensor, 23 spline, 0.75:1 OD
* 87-90 6cyl: one speed sensor, 21 spline, 0.70:1 OD
* 87-90 4cyl: one speed sensor, 21 spline, 0.70:1 OD, different bellhousing but I *think* it's otherwise like the 6cyl 87-90 one. Torque converter may also be different.

The 97 AW4 has a different electrical connector than the 91-96 but is operationally the same, all you have to do is splice your connector from the old tranny onto the new one and you are good to go.

And yes, the initial post in this thread is pretty inaccurate.

 

[Explorer 1]

Great Thread, thanks for all the reseach and information!

BTW, As of April 1990 they were still 21 spline.

Someone once told me that the AW4 was the same transmission found in the old Toyota Supra Turbo and it could easily handle 300+ Lbs torque, anyone able to confirm? :dunno:

Thanks,
Fred
Explorer 1

 

[joe_peters]

It is used in various Toyota vehicles as the A300 series:

http://en.wikipedia.org/wiki/Toyota_A_transmission

 

[CaliGold]

As Joe said, used in lots of Toyota and Lexus vehicles as the A340. In fact, they are available today in the current Toyota Tacoma 4 cyl models.

 

[MJR]

87-90 are 21 spline and the OD ratio is 0.70
91-up with a 4 cyl are 21 spline
98+ use an input speed sensor in addition to the output.

 

[kastein]

I've literally never seen a 91+ AW4 4cyl, they made those?!

(I knew 91+ AX5 4cyls were still 21 spline, though.)

 

[cal]

I've seen a couple.

 

[MJR]

I've literally never seen a 91+ AW4 4cyl, they made those?!

Yup. A quick search on Autotrader turned up a 94 and 99. I believe the last two years 00-01 were all 4.0L automatics.

http://m.autotrader.com/cars-for-sa...es=&keywords=&&lastAccessedTime=1397163355302