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-   -   manual to auto swap (http://www.wranglerforum.com/f210/manual-to-auto-swap-14381.html)

350chevrolet 12-28-2007 06:16 PM

manual to auto swap
 
how hard is it to swap a 98 sahara from manual to auto? i just bought this 98 sahara with 80k miles and a 5-speed. even tho i love 5-speed and thats almost all i drive, i want to swap the jeep to auto so that my girl friend can drive it and because i like auto when wheeling. is there a huge amount of fab work that needs to be done or is it a direct swap? will i have to do anything to the ecu? can i swap in a 03 auto (4-speed) or do i have to go with a 97-02 auto (3-speed)? doing the work is not hard for me i just want to know what im getting myself into before im in the middle of it. so far the parts i can think of that may have to be changed: trans, transfer case, shifter, flywheel, starter.

Jerry Bransford 12-28-2007 06:40 PM

The 3-speed will be a lot easier than the 4-speed auto used in 2003 and newer TJs. That particular auto has a lot of electronics to it and it's not easily interfaced into an older TJ. Another 4-speed automatic alternative is the AW4 used in the Cherokee. It's a fairly popular swap that is a little more involved than the 3-speed auto, but not as difficult as swapping in that newer TJ 4-speed... which isn't getting much praise for how well it works anyway.

Here's a great writeup from the getting famous Stu Olson on how to do the AW4 conversion... http://www.stu-offroad.com/engine/aw-4/aw-4-1.htm

Personally, I am taking the easy way out and installing the 3-speed automatic used in the early TJs. I've got everything for the conversion which I'm starting in mid-January.

AzTJ 12-28-2007 06:49 PM

You shouldn't have to swap transfer cases, and the only other thing is the transmissions PCM(computer) because it is electronically controlled.

Jerry Bransford 12-28-2007 07:37 PM

Quote:

Originally Posted by Jerry Bransford (Post 176191)
The 3-speed will be a lot easier than the 4-speed auto used in 2003 and newer TJs. That particular auto has a lot of electronics to it and it's not easily interfaced into an older TJ. Another 4-speed automatic alternative is the AW4 used in the Cherokee. It's a fairly popular swap that is a little more involved than the 3-speed auto, but not as difficult as swapping in that newer TJ 4-speed... which isn't getting much praise for how well it works anyway.

Here's a great writeup from the getting famous Stu Olson on how to do the AW4 conversion... http://www.stu-offroad.com/engine/aw-4/aw-4-1.htm

Personally, I am taking the easy way out and installing the 3-speed automatic used in the early TJs. I've got everything for the conversion which I'm starting in mid-January.

One thing I forgot to mention if you go for the 3-speed automatic is you'll need a different ECM (engine computer module), one from an automatic equipped TJ from your same year. That's required to provide the lock-up signal to the torque converter.

AzTJ 12-28-2007 07:41 PM

Beat ya to it Jerry. :D .... well kind of.

MR.CLIFFORD 12-28-2007 08:19 PM

Quote:

Originally Posted by Jerry Bransford (Post 176191)
The 3-speed will be a lot easier than the 4-speed auto used in 2003 and newer TJs. That particular auto has a lot of electronics to it and it's not easily interfaced into an older TJ. Another 4-speed automatic alternative is the AW4 used in the Cherokee. It's a fairly popular swap that is a little more involved than the 3-speed auto, but not as difficult as swapping in that newer TJ 4-speed... which isn't getting much praise for how well it works anyway.

Here's a great writeup from the getting famous Stu Olson on how to do the AW4 conversion... http://www.stu-offroad.com/engine/aw-4/aw-4-1.htm

Personally, I am taking the easy way out and installing the 3-speed automatic used in the early TJs. I've got everything for the conversion which I'm starting in mid-January.

Quote:

Originally Posted by Jerry Bransford (Post 176209)
One thing I forgot to mention if you go for the 3-speed automatic is you'll need a different ECM (engine computer module), one from an automatic equipped TJ from your same year. That's required to provide the lock-up signal to the torque converter.


Everyone step back. Jerry is now talking to himself. Bad things are about to happen. :D

350chevrolet 12-29-2007 09:56 PM

so is the wiring harness in my tj allready set up to accept the 3-speed auto or does Jeep use a different harness for the manual and auto? my bmw when i swaped it from auto to 5-speed was just plug and go since the auto harness and the manual harness were the same.

Jerry Bransford 12-30-2007 11:54 AM

You only need the Reverse light switch and the connection for the torque converter lockup and yes, both of those are in the wiring harness. The lockup connector is actually already dangling near where it needs to be plugged in. You only need an ECM that came out of a similar model TJ but with an automatic transmission to make that torque converter lockup wire work. :)


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