I have a 89 XJ with a 4.0 and it needs a new engine, can I put any year engine in it?

 

Are you doing the work or having it done?

 

The blocks are the same so if you just used the long block you will be fine. Try running a search. there are tons of threads on here talking about motor swaps

 

The short block from an XJ/MJ/ZJ and probably YJ should bolt right up, but the short block dosesn't include the head.

The long block (block assy + head assy) gets a bit dicey, since that cylinder head was only in use on two models for four years. 1987-1990 XJ/MJ, to be specific. Whether or not you can get away with converting depends on how difficult the Air Police are to you - if you're not subject to regular checkups, you'll probably be fine.

There are myriad articles and threads on a number of boards and sites that will detail the installation of an HO (1991-2006) head to work with the RENIX (1987-1990 XJ/MJ) control system, so I won't go into detail at the moment.

Good luck!

Oh - the short block from the YJ and TJ may or may not fit - I'm reasonably certain that the block mounting to the chassis was changed, but it's not soemthing I'd swear to in court at the moment.

 

Its backwards but I have a 88 block and head in my 91.(it was free and I needed it. lol)