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What year 4.0L moved the oil filter adapter

BIGSLVRXJ

NAXJA Forum User
Location
Des Moines, Iowa
Does anyone know with certainty what year 4.0s had the new oil filter location? I know most if not all WJ 4.0s had the new style where it screws directly to the block but I've also heard some 1998 ZJs did.

A shop swapped a 4.0L into my friends 1997 XJ and it has the higher location with no adapter, which is something I would love to do to mine. However, I always thought it was WJ (and possibly TJ) only engines which is not something I want to get into (head problems, accessory swap, etc.)

Any insight would be appreciated.

Thanks,
Collin
 
IIRC YJs also have it right on the block. But that's because they have a wider frame rail spacing than cherokees iirc and can get away with it and still be able to service the filter.

All XJs have an adapter, some face to the back and use one thread and others (92 or 93 or so and earlier? unsure) have the filter facing up and use a different thread.
 
I know that all XJs have the adapter, sorry for the confusion. In the later year 4.0s (not in XJs) they physically changed the location not just eliminating the adapter but also moving it further up the block. I'm trying to figure out if this started in the WJs or if TJs or possibly 1998 ZJs had them that way also. YJs would have just had them screwed the same location XJs have them without the adapter.

This photo illustrates the difference I am referring to


I just looked up on a parts store website and it looks as though 98 Grand Cherokees had a specific 4.0 to themselves. But in WJs they continued with the higher mounted filter location.

I know that I can remove the adapter and use a smaller filter and keep my fingers crossed that it doesn't get crushed by the motor mount arm but I would just like to know for future reference so if I grenade an engine I can look for one with the relocated oil filter boss.

Any additional insight on this would be appreciated.

Thanks,
Collin
 
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That's rather odd. I am pretty certain the engine in my 91 MJ (which came from a 96 XJ, but was put there by a friend of mine, who got it from a junkyard 98 ZJ) has it in the normal spot.

Maybe it is a matter of model year vs production year. I'll check the factory parts catalog in a few.

edit: the part number, 04883025, for the 4.0 block in the 97 and 98 ZJ factory parts catalogs are exactly the same.
 
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That's rather odd. I am pretty certain the engine in my 91 MJ (which came from a 96 XJ, but was put there by a friend of mine, who got it from a junkyard 98 ZJ) has it in the normal spot.

Maybe it is a matter of model year vs production year. I'll check the factory parts catalog in a few.

edit: the part number, 04883025, for the 4.0 block in the 97 and 98 ZJ factory parts catalogs are exactly the same.
Okay, when I checked O'Reillys website for the engine block the 1998 ZJ was by itself. But I know for a fact most if not all WJs had it higher and to the rear. Again the new location eliminates the need for an adapter, even in an XJ, and you can still run a full size filter, which is awesome.
 
That's pretty cool, I wish WJ blocks fit XJs easily. Personally, I have a remote filter setup waiting to go in, but I haven't felt like installing it yet.
 
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