My 1999 4.0 Jeep TJ has the Champion plug RC12ECC right on the label under the hood. I ve been running these and typically change them at 40-50K miles and they still look great. Gap might grow a little but can’t see a change in engine performance or measurable mpg. Due for another plug change and just seeing if anyone has any new and improved recommendations before I get the plugs?
BTW I m the original owner and just crossed 200K and not one spark plug problem to date.
Thx for any comments or confirmations to stay with the same plugs.
BTW I m the original owner and just crossed 200K and not one spark plug problem to date.
Thx for any comments or confirmations to stay with the same plugs.