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will a pre-2000 4.0 bottem end swap into a 2000 XJ?

semisynth

NAXJA Forum User
Location
PA
will a pre-2000 4.0 bottom end swap into a 2000 XJ?

I just rebuilt the top end of my 2000 XJ's 4.0 only to find that the bottom end is also hosed. I can't find a 2000 4.0 to swap in so I'm looking for options. Will a pre 2000 4.0 swap in if I use my 2000 head? Does the engine have to come from an XJ? I can get a '93 4.0 w 100k for $350 should I go for that or get the '99 w/40k I found for $650? What do you guys think?
Thanks for any help.
 
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i belive the 99 / 00 are the same casting, i actually forget when they change casting,
 
Other than some NVH stuff the block should be the same.
They put a girdle on the bottom at some point betwwen those years, it could probably be moved from your engine to the donor if needed.
The basic block should be the same though.
 
from what I encountered when I did my engine is that 91 is by itself 92-93 are together and then I think it is 94-98 being the same. I would say no you can't use the 93 bottom end. Call a local yard that you are friendly with and they may help you out using the Holland exchange book. It has all of the compatabilities listed.
 
For the difference of $300, I'd go for the newer motor with less miles regardless of compatiblity..
 
The '99 block should be the same. In '96 they changed the block. The previous mentioned stiffening of the block and girdle were some of the changes. They also, added dowel locators to position the head on the block. There might be differences in the Serpentine belt setup. Still, you probably could use the earlier block. My main concern would be the serpentine belt setup. The vehicle type shouldn't matter. I did run into someone who had problems with a newer block swapping into a '95 Wrangler. I remembered it being an '00 block. I did swap in an '03 block. The motor mount bosses were different. I had to modify one of the motor mount brackets, and use a spacer on one side. I do have an '00 block sitting in my garage. The motor mount fits my '88 engine (I had) and the '95 block. The '03 was out of a GC.
Tom
 
Thanks for the replies guys. I ended up making a deal for that '94 engine. I traded a couple of parts trucks and $125 for it. I just got it and I'm going out to take measurements to make sure the motor mounts will line up. I'm also going to check if the accessories and brackets will swap letting me use my 2000s belt setup but if not the '94 came with everything but the alt. and AC compressor so I should just be able to go with the old style without much hassle if need be. If it doesn't seem like the '94 will swap without much if any fab. I'll just have to get the '99 and use the '94 for a spare for my '94 XJ or maybe build a budget stroker out of it. It looks like I'll have to buy another cam if I want to swap all of my other new parts (lifters, push rods, rockers) into it but at this point I think I'll just inspect those parts on the '94. If they are still in good shape I'll just reuse them and save the new parts to eventually rebuild/stroke the 2000. Hopefully I'll be able to just reseal the '94 with all new gaskets, swap heads, rockers & push rods, change the belt setup, and bolt it up.
 
TacticalFats said:
How did you kill the motor in the first place?
Sudden massive oil loss was what did it in. Probably the result of an accident it was in where some clueless lady ran a stop sign and plowed into the passenger side front wheel smacking the uca axle mounts into the oil pan disturbing the the seal. It went 60000 miles before the seal blew at 130k.
 
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