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ZJ AW4 swap Issues. Need input!

NW-ZJ-SCOTT

TEXAS-JT-SCOTT
NAXJA Member
Location
NE Texas
So i got a free 93 4.0 ZJ with a bad transmission..

I bought a low miles Aw4 out of a 98 XJ

after today, i've come to the conclusion the tranny in my 93 ZJ is NOT the same as my 98 xj AW4. Nor does it look anything like the 88 AW4 i have laying in the garage.

The tranny pan is different, the Tranny lines are on the opposite side. and the sensors are in different places..
I've come to the conclusion somebody has swapped it out before my Ownership.
What do i do? Is it a straight forward swap on sensors and tranny lines? or do i find another tranny that matches the old one?

Below are pictures of both trannys (old and new) :(
Current bad tranny
DSC00433.jpg

DSC00434.jpg


New tranny i bought as replacement
DSC00442.jpg

DSC00453.jpg

DSC00445.jpg



:gonnablow
 
That original tranny is probably a ChryCo 42RE. The AW-4 was only used in the early-93 ZJs, 93.5 and up they used the 42RE instead.

93-93.5 the ZJ, XJ, and MJ AW-4s are exactly the same and even share the same part number however.

I bet if you swap some wiring harnesses and the ECU as well as the TCU and transmission, you will be golden.
 
Kas is correct on the AW-4 being just early 93.. if you dont have the 1-2 position on shift bezel yours started life with a 42re.

I'v never seen one converted and 100% operable yet. Theres a few threads at Mallcrawlin on an AW4 swap if you wanna look into it.
 
I've always wanted to buy a late model ZJ and swap in an AW4. Those 42re's suck rocks! I don't think anyone could convince me that dumping the AW4 was a good idea for the ZJ.
 
Well. It throws a curve ball for now, I was planning on having this rig up and running this week, New goal is end of the year.. lol

A 93 ZJ with a bad tranny has the resale value of a brown soggy apple. so im just gonna stick with it. the last thing i will do is buy another 42re.
 
Looks like you'd need to swap out the ECU and possibly the wiring harness for the engine compartment and/or instrument panel... not sure, something changed on build date 7/16/92 and I'm not sure what. The ECU part numbers are different for the AW and "electric shift" transmissions though.

You could always hack it up and make it run with an XJ 4.0 manual ECU + wiring harness but it's gonna be a hell of a project and the dash+BCM related stuff will be a real party.

(this is all parts catalog trolling, I have no actual experience with this swap thus the uncertainty)
 
How about an AX15 swap?

Will at least save you the electronics hassle.
 
Fixing a 42re is like fixing a d35, they suck. Friend of mine with a ZJ has had his go out 3x now.
 
Repairing or replacing the 42re is not an option. Mainly because of cost. I have 2 Jeeps that demand all of my money, this is just a cheap budget build for my father. so a $1-200 tranny swap is one thing, but a $1500 rebuild is not happening. Especially with the 42re's Bad reputation.
 
A rebuild kit and torque converter would only run about 250$.
 
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