I'm getting ready to change spark plugs on my JK. I'm currently on my 2nd set, which were OEM Champions. Anyone run anything else in the 3.8 that they like? I'm not looking for any big performance gain, but the OEM's seem to work well for about 40k, then I start getting a bit of knock/ping, as the gap widens. I'd like it if they lasted longer. They are relatively cheap, though, so no biggie. I just want to see if other brands, like NGK or Bosch have fared better and longer than the stock Champions. I've got premium lifetime guaranteed wires, so I'm just looking at plugs. (Not interested in Split Fire plugs, or other gimmicks, if they still even make those.)

 

I am approaching 100k looking to do it all, wires, plugs, o-sensor, ignition coil. I will scout the site for past discussions but recommendations welcome. PS Merry Christmas and Happy New Year or Happy Holidays if that inflates your tires.

 

I've been having good service from the OEM plugs. I changed them at about 50K miles to make sure they would not "welded" in if I waited until the 100K interval.

I didn't see any larger gaps. There have been more than a few posts about the gaps not being properly set from the factory, though.

 

Then that would explain mine. I've only checked my original set, and the gaps were wider. I just assumed they widened with use. I may pull one just to check it. I know these were right when they went in, as I set the gaps when I installed them.

 

OEM are platinum and it is recommended to stay with the oem. There are several threads on problems occuring from using "performance" plugs if you do a search.

 

Agree with Dirtman here. Also, ALWAYS check gap on any plugs you're installing. Plug part numbers have multiple applications with varying gap specs so you can never assume they're "pre-gapped".

All that to say, we've run NGK and Bosch in many race applications with great results. I've never been a fan of Champion, personally. However, I think aside from some longevity concerns, anything more than stock in these Chrysler V6s is a complete waste of money. You'll never get any big performance gains anyway from spark plugs unless you're replacing bad/wrong or mis-gapped ones for ones that are correct and gapped properly.

 

E3 plugs gave me an additional 2mpg and still do over 2 years later

 

Yours is the only post I've seen that didn't say the E3's caused problems with the 3.8L engine.
Did you get the additional mpg right after installing them? What time of year was it?
And how many miles on the OEM plugs at the time?

 

Mmm yeah okay... Sounds like you bought your plugs from my Nigerian Uncle Mohammed

 

My patented 'Magic Beans' and patent pending 'Snake Oil' usually results a 20% increase in mileage without needing tools to install
Boxing day pricing until next Christmas.