Spark plugs 04 Grand Cherokee

4.7HO engine. Can I replace the platinum plugs with copper core plugs? (Champion RC7PYCB4 to NKG BKR7E)

I highly recommend that you stick with the original manufacturer plugs in an equivalent heat range. You can switch and if you are lucky, they will perform fine, but you just waste a lot of time and money if they don’t.

Copper plugs are fine, but they won’t last nearly as long so you will be under the hood doing them again much sooner.

Can I replace the platinum plugs with copper core plugs? (Champion RC7PYCB4 to NKG BKR7E)

I would recommend staying with the OEM brand and heat range. The cooper plugs should work as well, but not last as long. Plan on replacing them at least twice as often as recommended in the owner’s manual.

Actually, copper plus should last only 12K miles, while the platinums should hold up for 60K, even tho most manufacturers state 100K in the manuals. This is 5-9 times as long. The platinums in our Ford Explorer are $7.00 apiece from Ford, but copper plus typically cost $1.50 to $2. Using platinums have been saving us money in the long run.

Copper core plugs only lasting 12k miles? If copper cores are failing after 12k miles then there is something else causing it; it’s not the fault of the plugs.

If the engine is not burning oil and the engine controls system is fine copper cores should easily go 30-40k, or possibly more.

I have been using copper core plugs for years and get 40,000 miles out of them. I would also add I dislike the champion plugs do to poor quality. I have seen way to many cracked champion plugs.
~Michael