i just picked up a 1999 xj sport with 168k on the clock with the 4.0 and auto trans. the engine is bad in it and the previous owner had already started pulling it out, the head has already been taking out and the only thing left is the two top bell housing bolts and the motor mounts. my question is what should i look for when buying a used engine? i know it has to be one with a distributer and wires since thats was it has and not the coil pack version. is there anything i should do with the engine out of the vehicle, upgrade wise. any help would be great as im going to start looking for a new one in the next few days. thanks again everyone.

 

I'm not the best one to ask about year interchangability, but personally I'd stick with a '99 or possibly '98 engine if you are planning on swapping everything, sensors and all.
97 I'm not familiar with, might work? '96 is an oddball. Prior to '96 is OBD1 creating another headache.

 

okay, hopefully more people will chime in!! thanks again

 

What exactly is being swapped? Any XJ or ZJ block will work. Even most heads are easy to deal with. If you're keeping your electronics and accessories you have a lot of options. Though any 2000+ XJ engine on the used market is probably there thanks to damage from a cracked head. Lol

 

The 1997-1999 engines should be almost identical. There are a few small differences, but not many. That would be your best bet.

As the previous poster said, if you are looking for just the block, etc., then any HO 4.0L will work, and you can use all the accessories off your old engine.

Greg

 

im just looking to get it running and if it runs well im going to lift it and put wheels and tires on it. the head has been setting outside but under a tarp so im sure it will have to be sent to a machine shop. and all the accessories are still in the vehicle and im sure all the electronics are aswell. so basically i need to look for a 97-99 engine? i replaced a engine in my 99 cavalier awhile back and the engine i bought i was told by the salvage yard was identical and out of a 2000 model and alot of stuff was different. i was not even able to use the knock sensor without drilling and tapping the block. this is why i am asking.

 

No knock sensor on High Ouput 4.0s. If you just need a new block its really simple.

 

True story. Knock sensor is Renix stuff. Are you done yet?