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does a 1992 4.0 2wd comanche come with the two wheel drive aw4? if so are the transmission harnesses the same between that and a four wheel drive aw4? looking to buy a 2wd comanche and swap it to 4x4, i understand almost everything i need but I'm not sure about the transmission. New to the topic so please understand i am a newbie. 

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I believe all year aw4 trannys have the same splines and harness connectors, but I'm not sure. If it's a floor shift aw4, it's a safe bet that's what you'll have to convert to, unless there is a writeup somewhere on how to convert a floor shift aw4 to column shift. You can use the front driveshaft out of any 4wd XJ with an aw4.

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You can keep the column doing the same conversion myself with a 91. Find a 91-96 aw4 for a plug and play later years will work with minor wiring harness changes there is a great naxja link that would help just Google aw4 trans its something like "everything you ever wanted to know about aw4" very informative. Yes the front driveshaft will work from Cherokee and try to find a non cad Dana 30 HIgh pinion look for a 99 xj to pull that from

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does a 1992 4.0 2wd comanche come with the two wheel drive aw4? if so are the transmission harnesses the same between that and a four wheel drive aw4? looking to buy a 2wd comanche and swap it to 4x4, i understand almost everything i need but I'm not sure about the transmission. New to the topic so please understand i am a newbie. 

 

There is some bum dope above, I'm not going to sift through it. Yes, the 2WD MJ will come with a 2WD AW4. In order to modify the 2WD AW4 for 4WD, you will need to swap out the 2WD tail extension for the 4WD transfer case adapter. This will require a different output shaft to adapt to the transfer case, and a complete teardown of the 2WD AW4. Not economically feasible. The best option is to swap in a 4WD AW4 from a donor. Then do the transfer case swap etc..

 

The MJ AW4 transmission harnesses are not the same physically, but functionally are the same. It can be cut and spliced to work, but the sensors like the speed sensor moves from the 2WD AW4 tail extension into the transfer case and other differences, so again it makes sense to use a harness from a 4WD w. AW4 92-95 XJ or 91-92 MJ donor.

 

Other things that need to be addressed are the ECU; the 2WD and 4WD ECUs are not the same, likewise for the TCU (transmission control unit). The connectors are the same, but their function internally is different for 2WD vs. 4WD. Another good reason to use a harness from a 4WD XJ or MJ to save you grief on the wiring and keep it simple.

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does a 1992 4.0 2wd comanche come with the two wheel drive aw4? if so are the transmission harnesses the same between that and a four wheel drive aw4? looking to buy a 2wd comanche and swap it to 4x4, i understand almost everything i need but I'm not sure about the transmission. New to the topic so please understand i am a newbie. 

 

There is some bum dope above, I'm not going to sift through it. Yes, the 2WD MJ will come with a 2WD AW4. In order to modify the 2WD AW4 for 4WD, you will need to swap out the 2WD tail extension for the 4WD transfer case adapter. This will require a different output shaft to adapt to the transfer case, and a complete teardown of the 2WD AW4. Not economically feasible. The best option is to swap in a 4WD AW4 from a donor. Then do the transfer case swap etc..

 

The MJ AW4 transmission harnesses are not the same physically, but functionally are the same. It can be cut and spliced to work, but the sensors like the speed sensor moves from the 2WD AW4 tail extension into the transfer case and other differences, so again it makes sense to use a harness from a 4WD w. AW4 92-95 XJ or 91-92 MJ donor.

 

 

 

Other things that need to be addressed are the ECU; the 2WD and 4WD ECUs are not the same, likewise for the TCU (transmission control unit). The connectors are the same, but their function internally is different for 2WD vs. 4WD. Another good reason to use a harness from a 4WD XJ or MJ to save you grief on the wiring and keep it simple.

 

Swapped in 95 aw4 and transfer case plug and play 2wd ecu and TCU works perfectly

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That's news to me I thought the ecu and TCU were basically the same only difference in harness that i can tell is the 4wd light on dash not doubting you but mine seems to be running fine with 2wd TCU and ecu

 

I did not say the 2WD and 4WD TCU and ECU would not work or not run in either configuration, I said they are different. I'm not doubting you either. I have no idea of the internal differences of either module. But, to avoid OBD1 fault codes, the TCU and ECU modules should conform to the specs of the drivetrain they were designed for. Have you tried checking for fault codes on your rig?

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I did not say the 2WD and 4WD TCU and ECU would not work or not run in either configuration, I said they are different. I'm not doubting you either. I have no idea of the internal differences of either module. But, to avoid OBD1 fault codes, the TCU and ECU modules should conform to the specs of the drivetrain they were designed for. Have you tried checking for fault codes on your rig?

 

I don't think I'm getting any codes though i havent checked? Ill get my service books out tomorrow I believe that the 4wd tcu and 2wd is the same model/part # could be wrong on that

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There is no need for a Cherokee harness swap u can if you want that's up to you this truck is a simple straight forward 4wd conversion JP magazine did a write up on this Google it they did it with junkyard parts step by step write up

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ok. id like to avoid it if possible but i was just saying lol. if no codes are thrown and it works perfect thats great. also i read on a different thread that both shifters can be used with the aw4 transmission, id like to leave column shift. could you check the part number for the tcu? thanks

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You'll want a 92-96 AW4 from a 4wd Cherokee. Those are truly plug and play.

Column shift should work fine. Shifter arm on the transmission may be different and if it is be very careful taking it off as they tend to shear the shaft if you're not careful.

 

I put a 96 AW4 into my 92 2WD Cherokee, there isn't any codes and it shifts fine. Also my ex 2WD 92 MJ is running a 96 AX15 with just the 2WD wiring and ECU with no codes.

 

The wiring harness works fine the way it is. Speed sensor wire is long enough to hook up to the new location on the transfer case.

 

You'll want a front driveshaft out of the same vintage but most 90-99 6 cylinder automatics should be the same. 

 

92 and up Dana 30's are non disconnect. 96-99 will have the larger Ujoints. 00-01 are low pinion axles so don't bother with them.

 

For the Transfer case shifter there is already a hole for it you just have to remove a plate. If you have a hard time finding decent linkage for the shifter Novak Adapt makes a cable shifter that looks pretty sweet.

 

What's your location?

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You'll want a 92-96 AW4 from a 4wd Cherokee. Those are truly plug and play.

Column shift should work fine. Shifter arm on the transmission may be different and if it is be very careful taking it off as they tend to shear the shaft if you're not careful.

 

I put a 96 AW4 into my 92 2WD Cherokee, there isn't any codes and it shifts fine. Also my ex 2WD 92 MJ is running a 96 AX15 with just the 2WD wiring and ECU with no codes.

 

The wiring harness works fine the way it is. Speed sensor wire is long enough to hook up to the new location on the transfer case.

 

You'll want a front driveshaft out of the same vintage but most 90-99 6 cylinder automatics should be the same. 

 

92 and up Dana 30's are non disconnect. 96-99 will have the larger Ujoints. 00-01 are low pinion axles so don't bother with them.

 

Well said

 

For the Transfer case shifter there is already a hole for it you just have to remove a plate. If you have a hard time finding decent linkage for the shifter Novak Adapt makes a cable shifter that looks pretty sweet.

 

What's your location?

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Frank is there a difference in the 91? I have a 91 with a 95 aw4 no issues plug and play or is the difference in the 91 xj? Thanks just curious

 

The only difference may be in the match up of the torque convertor to the back of the crank.

I don't know if there is a difference in the autos but I do know that there is one in the manuals so those are the years I stick to with the autos because I know that they'll work.

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I converted from 2wd BA 10/5 to AW4 in my '87. I swapped the underhood harness for one from a '90 XJ and used the XJ trans controlled. The ECU is still the 5 speed one. Works the same as any other AW4 XJ or MJ I've driven. The harness connector on the '89 MJ I parted is the same as the one on my '88 XJ trans I put in. There is an added crossbar on an angle from under the tcase to the frame for the MJs.

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