ok i'm about to replace the spark plugs. but i'm not sure what i should set the gap to. any help

 

Pretty simple search:

https://www.cherokeeforum.com/f2/nic...writeup-17956/

It's for a TJ but the same conditions apply to the XJ:

http://jeephorizons.com/tech/spark.html

 

you can buy most pre gapped... ".35" i think is the right gapp number

 

wat he said is true. most haynes manuals will say the same thing, for either the 4.0 or the 2.5...

 

always always check the gap. Really no such thing as pre gapped if they can be physically gapped. saying there pre gapped is stupid wait they were gently place in the shipping box at factory oh ups fedex they never toss a package oh and the idiot at the parts store is so dam careful too, come on now lets get a clue always check the gap on a plug. (stupidity is a right stop abusing your rights)

 

LOL

thats what I was gonna say, you just said it alot meaner

 

Also, Most jeeps (most cars in general) have data like that printed on a sticker under the hood.