rrl0044

1st time user, so please be gentle if this post is repetitive, in the wrong place, etc...

Alright so here is my situation...

I currently have a 2000 xj 4.0 with aw4 trans, Low mileage and a well maintained motor. I would like to swap into it an ax-15 transmission. My primary concern however is the ECU. If I am not mistaken the ECU on a 2000 xj also functions as the TCU. If I were to come up with all of the mechanical components and properly installed the ax-15, would there be an issue with the automatic ECU because it has no automatic transmission to connect to? I would imagine that the ECU would be looking for information from the trans that would not be there after this swap. Would this cause the motor to act outside of what I would want it to do when driving stick?
A friend of mine has an 87 xj 4.0 motor and 5 speed trans that he is willing to give me. Would taking the computer from his motor be a reasonable fix if the ECU does not like the manual trans? Or has the motor changed too much over the years to the point where the ECU's act too differently?
The reason I do not want to use his motor and trans is because I have read/heard that that year had leaky motors and the ****-poor Puegot trans.
I am fairly confident with my ability to do this swap as far as the mechanical aspect goes, but I am concerned about the electricals. It is quite difficult to cross reference them so I am reaching out to all you jeep guys for some of your experience based knowledge.
Let me know what you think.
Thanks!

Parsnip

Alrighty, here we go,

Firstly, no, the 87 motor and trans is a no go. That years trans is crap, the running system would make your jeep very unhappy. An ax15 swap is done by 1) getting a 95+ ax15 with an external slave cylinder, 2) getting a flywheel for your motor year, 3) clutch kit for your motor year, 4) getting an ecu for a manual jeep, or having yours 're flashed/reprogrammed.

DualSportDad

There is so much to change out you're better off buying a complete donor vehicle. I bought a complete 5 speed 98xj to swap my 97 over to a ax-15. It was a lot of work.

Parsnip

It's really not though

salad

There are huuuge differences between 2000 and 1987 model drivetrains. The engines themselves can be swapped but everything else is incompatible.

The biggest technical hurdle is getting the CEL to turn off if you have OBD-II emissions testing. If you don't, and the light doesn't bother you, you don't need to do anything at all. The PCM just throws a code complaining that the TCU doesn't respond - or the TCU throws a code directly. They are not integrated in an XJ. I believe you can silence the TCU by attaching resistors to the outputs so it thinks everything is okay. The other approach would be to get a PCM from a manual XJ but, depending on emissions, this can be bery hard. Most 2000+ systems have additional O2 sensors and cats that earlier models did not, and manual transmissions were quite rare. If you just have a single cat you can again technically use an earlier PCM but the wiring is different on account of change from distributor to coil-on-plug ignition.

XJwonders

and not to mention that they changed the trans in 2000... 1999 was the last year they used the AX15

Parsnip

Going from a manual to an ax15, regardless of year, is very, very simple

salad

That doesn't matter lol. The reverse switch might be different... Oh no...

That would be because an AX-15 IS a manual!

Parsnip

Derp

Auto to manual is easy, I've done 2 on a 90 and a 96, they are really easier then a high school floozy

DualSportDad

Trans, flywheel, clutch, drivasafts, 4wd linkages, engine harness, engine bay harness, ac pressure switches, air bag module, steering column, ecu, master and slave cylinder, ignition coil, cam sensor. That's just off the top of my head.

salad

...what? Maybe to swap an entire 2000+ drive train

Parsnip

Fixed it for you.

DualSportDad

OP, if you must want the trans in your car then by all means just do what this guy says. If you want it in your jeep and working properly, like the factory then do yourself a favor a buy a donor jeep.

Buying a donor jeep you'll probably come out not spending any money anyways. I bought my 98 for $400 and sold some parts off of it and scrapped it and made double my money back.

A friend has a mj with a 5 speed and we are going to swap a ax-15 into it. We bought a clean running, driving, with a/c 91 2 door XJ for $1000. After taking the bits we need he expects to part it out for close to what he paid for it.

Parsnip

Look, I'm just saying, from experience, you can get a factory functioning ax15, pedal assembly, flywheel, clutch set, master and slave, and be in under 400$. There's just no need for the whole Cherokee to do the swap. The trans harness can just be folded back and taped up (or cut), the nss just gets either bypassed or a simple pressure button switch tied into it, and the reverse lights is only 2 wires to splice. That's just how I did mine and another one, but, if you want a whole donor (if it's running and driving I wouldn't sacrifice it just for the trans) then that's your deal

DualSportDad

Not sure where are from but around here (and everywhere else I looked) the ax-15 alone is more than $400. Let's say you get driveshafts for $50 a piece, a clutch for $100, slave and master for $100, what does leave for a ax-15? Now let's remember you'll need the shifter, pedal assembly, shifter bezel and boot. No way you're getting all that for $400. Oh and wait... For some reason I remember needing the plate that bolts to the tunnel so there was enough room for the shifter to come through the floor.

I have a thread on this forum showing what I did when I did my 5 speed swap but most of the pictures aren't showing up. I'll go fix that and post the link.