Original spark plugs 2000 4.0?

[N8N_99xj]

Want to order plugs for my "new" Jeep but it's not here right now and I neglected to look at the emissions sticker (have to go to DMV before I can legally drive it, it's at my friend's shop because cops will ticket you if you park it here even in your driveway)

I see tons of threads saying "use the original NGK plugs" but what part number is that? I'm searching my little fingers to nubs and am finding narfin.

thanks!

 

[Johnnie Walker]

Rockauto or parts store site of your choice.. Look up your vehicle and find ngk platinum plugs

 

[Sidewinder CC]

Here's a spark plug application chart and a tech tips letter pertaining to the use of NGK ZFR5N plugs.

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[N8N_99xj]

OK cool so NGK ZFR5N it is then? that's the one that kept coming up when I looked, but I was unable to confirm that that was what was the factory recommendation.

Just out of curiosity what is the R1? Only thing that registers in my brain is the 1963-64 high compression NA Studebaker 289, and I'm pretty sure those never came with NGK plugs, and that's not a 4.0 either