91 AWD 5 spd to 90 AWD auto swap T/E

[240addiction]

I have found a donor car for my colt to go AWD and auto. currently I am running a 91 AWD 5 spd with a vce for just FWD use, but want to go auto and AWD from a 90. I have the complete 91 drive shaft, transfer case and rear end from the car I got my current motor and tranny from. The donor car has the complete tranny, transfer case, driveshaft and rear end only missing the output shafts. Which is my first question are the output shafts for the rear end the same as a 5 spd for an auto? what electronics will I need for the auto that my current setup does not have? New ECU? I assume the tranny mount will be different which wont be a big deal. What about the axles the mirage turbo axles fit the AWD 5 spd, but will they fit the auto tranny? how different are they? Any other advice would be helpful. Thanks in advance.
Paul

[sbiggi]

The trasfercase shaft is the same.

The rearend has a different ratio, so you need the correct ring gear and pinion.

You'll need the correct harness for the transmission and the TCU.

The intermidiate shaft on the driverside axles is a different size as well.

[Toybreaker]

I've got a few of the pieces you may need.

rear diff, with both rear axles from an auto awd, (upgraded to 4 bolt) the diff carrier bearings are tired, but the ratio is correct, and the axles are correct for a three bolt cup. (90 and 91 auto awd) Should be a good core.

An e-prom ecu for the auto tranny equiped awd.

And the tcu, (tranny control unit)

Let me know if you need anything,

John

[240addiction]

Will the drive shaft be the same?

will I need a 91 ECU and TCU or will the 90 TCU work? I assume I will need the ECU from 91. Will I need an entire harness or just the TCU and the wiring should be there? I have a a custom harness for the colt and would prefer to not have to make that change.

will the input shaft froma a 5spd 91 work in the auto 90 rearend?

[sbiggi]

Will the drive shaft be the same?

will I need a 91 ECU and TCU or will the 90 TCU work? I assume I will need the ECU from 91. Will I need an entire harness or just the TCU and the wiring should be there? I have a a custom harness for the colt and would prefer to not have to make that change.

will the input shaft froma a 5spd 91 work in the auto 90 rearend?

The only thing different on a auto ecu is the injector size. So it is not needed neccesarily.

The driveshaft is the exact same. I'm running the one off our 93 TSI Auto.

I'm not sure on the wiring, but the tcu reads the TPS so I imagine that you need the harness.

[240addiction]

well I pulled the tranny got the rear end and transfer case along with a TCU for 90 bucks. No wiring yet, but that will come next. Why are the shift kits for the 91-94 different for a 90, which of course is what I have. did they make a change between the two years?

[GSTinCO]

They did change the shifters after 90 and the 90 is built better. In the 90 shift kit you only get the base bushings, in the latter years you get another piece for the linkage.