i have ngk 5306 in my commander, thats 1 heat range hotter. i think it idles nicer and has better throttle response. i think it runs better with them than campions. im putting in some ngk 4306 in my rt this weekend, i will follow up with ya.
i havent come to the point where my plugs need changing yet in my 2010,but i can say this,i have just put ngk iridium plugs in my 73 440 challenger and i am very pleased with them so far.i spoke with a ngk factory rep at a sales meeting a while back and he gave me some literature that was very good explaining heat ranges and so forth.i had some trouble finding a good heat range for my fickle 440 and these iridium plugs have been the best so far over champion,autolite,ac platinums and even bosch.
was gonna put the 4306 in today. well they will run in my jeep commander its an 06. i think 09 and 10 went to a gasket plug. im trying to cross ref. found a ngk 6376 its a v-power and everything is the same but it dosen't project much like 4306 so i didnt buy them.they are for a 6 cyl infinity. but im still looking will keep ya posted.