McScruff420

1994 4.0 Grand Cherokee Limited
2001 4.0 Cherokee Limited

I blew a hole in the block on the 94, went through a puddle, got too deep and busted a hole in the side.

The 2001 was rolled and totaled, but the engine and drive-train should all be good.

What would I need to make this swap possible? I've heard it's impossible, I've also heard it's completely possible. If you guys could help me with as much info as possible that would be great.

Basslicks

Short answer is yes. The BLOCKS are compatible.

The 2001 uses a coil rail and coil packs versus the traditional single coil and distributor that the ZJs and earlier XJs use.

That being said, you should be able to just swap them over and use your current ignition setup.

I'm not sure if your 94 ZJ has a separate temp gauge sender from the coolant temp sensor (for the computer to read), if it doesn't you don't have to bother with it but on earlier XJs, they're separate... 97+ XJs, the computer sends the info to the gauge cluster.

If your transmission is good, use it. It will be quite a bit more involved to make the AW4 work in your ZJ. If it was a '93, it would be a little more simple.

You'll probably have to put the accessories side by side to compare what you need to swap around. It's definitely doable.

WARNING: Definitely ensure that the head on that '01 motor is NOT the 0331. If it is, you may end up replacing another motor. The casting on the 0331 head was weak from the factory and is prone to cracking - whether it's been overheated or not. If your head is still in good shape, you should be able to swap it over to the newer block... just be mindful of whether or not the "new" block has locating dowels on it for the head or not... I can't remember for sure, but I think the bolt holes in the head for those to locations are slightly larger.