My recently acquired 2006 3.7 Dak has a rough idle. From what I see on this forum, plugs are often the culprit. As I'm within a few thou of the 30Kmi change point for plugs, I figure I'll change them out. I've seen a number of posts mentioning Autolite 3923 but when I look up plugs for the 2006 the listing is for a 5224. Both are listed as the same heat range but different tip styles. For those with more experience with this beast, any comments? From past experience with many other cars, I won't use Bosch, especially Platinum. And I've normally had very good performance from NGK. But if my Dak has NGK from the factory, 28Kmi. seems terrible and I might go with something else.

I'm also curious why the heck plug changesare called for so often on this motor? It seems rather strange in this era of FI and direct ignition to need frequent plug changes!!!??? Heck my 63 Morgan with ratty old SU carbs & Lucas points & coil has gone 42 Kmi since it's last plugs & points and still runs as it should.

Thanks in advance for feedback.

Cheers,

Ken
2006 ST Quad 3.7 MT

 

the autolite is acctually one heat range cooler then the factory plug which helps out with the detonation. i had the 5224 in my 05 4.7 and lost between 45-50 miles to a tank of gas. these trucks dont like plats. but a nice copper core and they love them. for 10.50 for all 8 plugs at the localwalmart you cant beat the price, dont know why the plug change so much but thats what dodge wants. also most if not all the 05-07 daks came from the factory with bad plug gapping. you would pull one plug and it would be correct at .040 the nexted one would be .055 and the next, .035 so thats why these trucks shake a little at stop lights

 

As far as plug changes being often it seems pretty good for me, my last car went through a set of Vpowers every 12k or so.