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will an EJ TCU run AWD and FWD trans?


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huck actually installed a FWD into an AWD with no issues at all, BUT - this was in a 1990 OBDI vehicle.

any clue anyone if the 1996 OBDII stuff might be just as simple. i'm betting it is. i guess if the wiring harness is compatible i could as a last resort swap TCU's too.

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the circuit boards for the 95 leg sedan and the 96 leg wagon seem to be the same with one exception, the label on the main chip is different. i thinlk this indicates different programming. (the chip is the same but the printed lable is different.)

 

the 96 wagon TCU was not a good match for the 96 trans in the 95 sedan body. it shifted later, reved higher and wanted to stay in 3RD. i figured this was due to the wagon being heavier than the sedan, any thoughts? i think the the mechanics of most of the trans are pretty much the same, but the programming in the TCU is for the specific model size, weight and driving characteristics, such as GT sedan vs outback wagon.

 

i don't know if there is a physical difference between FWD and AWD TCU's, but the AWD TCU should be looking for the rear speed sensor.

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.I've only dealt with early stuff.The fwd tcu has less inputs and wires going to it.Some of the pins are different,these can be swapped.Yes fwd into awd most likely will work better than awd into fwd.Fwd tcu runs 2 speed sensors but they back each other up.Awd the speed sensors determins the amount of transfer front to rear, a fwd tcu can't do this.

The best advice i can give with auto's is run the right tcu for the box.

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  • 5 months later...

Okay I finally finished the swap - I installed a FWD auto into an AWD 96 Legacy LSi. Runs and drives but isn't quite right.

 

It goes, bogs down, goes, bogs down...very rhythmically and predictably.

 

I also installed an intake with no EGR on it - could that affect anything, I know the cars will run strange with EGR issues.

 

No CEL

The AT Light blinks at start up so I know it has some code.

 

I'll try and figure out how to check the codes - i never could pull the codes on an XT6 - hope this goes better!?

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Got the car running and shifting great today, so that's good news. We'll see how it does later on, if no issues present itself then I won't bother swapping TCU's. not sure how it will perform entirely since i just drove a few miles down the street, but the 5 mile test run was golden.

 

so yes - you can install a FWD transmission in an OBDII AWD vehicle without issues and without swapping the TCU and the car will run and shift fine.

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The AT Light blinks at start up so I know it has some code.

 

 

It is probably seeing the lack of a *C* solenoid as a failed solenoid. You may want to intall a resistor in place of the solenoid.

 

You may want to insert the FWD fuse as well. Might help it deal with the no AWD issue.

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