My 4.0 has 136k on it... I guess i should be pissed at the previous owners for not taking care of it!! But it sounds like a rod bearing going out and makes and inconsistent knocking sound.

My question is how hard are these motors to swap out?

I have swapped out motors in Audi's and VW's (which by the way were all above 300k miles)... Everything was always pretty straight forward.

Maybe i should just sell it and by another VW or Audi!

What needs to happen to convert the coil pack ignition system to a distributer style ignition?

Will i need a new ecu? Or main Harness?

WTF!!! NO WAY!!

It is straight forward, and if you can swap an engine in a German ride, then you can do a 4.0 blindfolded!!

I guess thats a good thing... But i guess im just scared of the new motor falling apart too...I always heard great things about the 4.0!! This engine is why i got my jeep!!

But im not very impressed... dont get me wrong i have fallen in love with the stupid thing!!

It's much more easy than u think, if u have swapped a Volkswagen or Audi engine u won't have any particular difficulties, there is much more space all around in a Jeep, in line Audi's fit fking tight, i remember those two damn bell housing bolts near the exhaust pipe being a real PITA.

What about the electronics? What changes will i need to make to the harness and or ECU/ECM?

I plan on buying an older engine... 97-99, because of the potential 0331 head cracking problem in the 00-01 engine.

There is plenty of information about motor swaps in here, take some time and patience to search the threads.

I guess i knew that was coming.

I have done quite a bit of research, But i dont think ive seen anybody convert to an older style ignition.

I am going from pre 91 engine to a 92 engine. Straight forward when swaping engines. As far as new jeep to older engine not really sure. Could see potential electrical problems.

This should make it clear to you. http://www.go.jeep-xj.info/HowtoEngineInstall1.htm

Thanks thats got some good info!!

I'm confused by why anyone would want to go to the older style ignition systems? ie. distruibuters.
It's another item that will WEAR out. I'm going to try to install the 2000 ignition in my 98! No distruibuter bearings No rotor No distruibuter cap. No parasitic drag on the engine to turn said distruibuter. Yes I know it's negligable but still!

I also can't think of why the ignition system would affect your choice of head on your engine. I haven't seen a 2000 cherokee engine yet but I can't believe that the head will have been greatly changed (other than the minor stuff that leads them to cracking) to use the more efficent ignition system. It's all bolt on I believe. Now I could be out to lunch here but knowing how much lead time to produce a change in a major system like that on a production vehicle would have made the Chrysler go with the simplest thing and just have it bolt on to the valve cover etc.
Anyone have any pictures of the newer ignition systems?

It wasnt the design that changed, it was the manufacturing process!

I believe that they were moved around while still temperingm, and this made them prone to cracking in certain instances.

BTW Dont quote me on this! this is what i heard.

Just swapped engines 2001 Jeep Cherokee Sport very easy swap found engine out wreck that had 70000 for $600 and one for $800 that look new 40,000 look for Jeep Cherokee that been rear ended and check miles. as for 0331 head they crack between #3 &4 cyl when they get way over heated. you haft to watch the temp. A 1996 to 1998 will work, with 2000 ignition system you have to make bracket for coil ignition replaced distributor with your 2000. A grand Cherokee will not work eng mounts and accessery are different.

before you go swapping motors check some of the things like loose torque converter bolts motor mounts trany mounts header down pipe power stering pump AC pump

4.0 can give you a rod knock sound for lots of reasons other than bad rods