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Discussion Starter #1 (Edited)
So while perusing my owner's manual (2013 R/T Classic) looking for transmission service information, I stumbled across a recommended spark-plug replacement at 30K miles. WTF?

Shame on me for not reading my manual cover to cover when I bought it. But after owning Hondas for 10 years, I became accustomed to 100K spark-plugs (and never kept any of them long enough to need them). Hell, even my 2002 Chevy Avalanche had 100K spark-plugs. I haven't put spark-plugs in a vehicle since my 1979 Chevy Pickup.

First, what's the deal with 30K spark plugs in an era when 100K is the norm?

Second, any advice on replacement plugs. OEM original? Any reasonable facimile? Any performance to be gained with a particular niche brand?

I've got 65K on my 5.7L and it still runs like brand new. Same 0-60 time (according to the on-board timer) as the day I brought it home. Nothing to make me suspect that I'd needed spark-plugs 35K miles ago.
 

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Yeah earlier years used copper plugs.

http://www.challengertalk.com/forums/f5/5-7-spark-plug-replacement-30-000-a-52762/

Easy to replace but if you change every 30K and don't use anti-seize on the threads you run the risk of damaging the threads (there is also risk of cross-threading) on the aluminum head. I ended up replacing the coppers with the iridiums that came from the factory on my 2015 RT when I dropped 1 heat range lower as I am running forced induction.
 

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Discussion Starter #4
Yeah earlier years used copper plugs.

http://www.challengertalk.com/forums/f5/5-7-spark-plug-replacement-30-000-a-52762/

Easy to replace but if you change every 30K and don't use anti-seize on the threads you run the risk of damaging the threads (there is also risk of cross-threading) on the aluminum head. I ended up replacing the coppers with the iridiums that came from the factory on my 2015 RT when I dropped 1 heat range lower as I am running forced induction.
I've looked at that thread, and others on other forums. Seems the opinions on spark plugs vary from

"You got 236K on the first set, why not put the same ones back in, they're obviously the best". to "Nothing but the original OEM copper or you'll be sorry".

Also horror stories on 8 hours to DIY to $800 for the dealer to do it.

Being ignorant of the spark plug replacement (something I thought had gone the way of the Highland Park Hummingbird), I had no idea the HEMI had two spark plugs per cylinder.

I'm pretty handy on changing my own brake pads, calipers, rotors, shocks, simple stuff like that. Replaced dozens of plugs back in the day when you did that every 15K miles when you got new points/condenser/rotor cap and plug wires. Not sure if I want to tackle removing coil packs and messing with seized plugs in an aluminum head. (I've got 65K on the factory plugs).

What's a reasonable amount of time for this job, and is is a "shade-tree mechanic" type thing.
 

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They used the copper plugs because replacing them at 30,000 miles made it easer and safer getting the steel plugs out of an aluminum head. they did not want to have the problems Ford has with the plugs braking or pulling the threads out of the head after sitting unmoved for all the years it took to go a 100,000 miles. And with 16 plugs there is twice the chances of that happening. It is important to change them on time as the plug wears the gap gets larger you don't have any signs like ruff running or poor performance because the ECU increases the burn time on the coils to jump the wider gap of the plugs witch will make your coils wear out much sooner then they should. Also the plugs should be put in dry if anti-seize is used and you use a torque wrench to put then in at the proper torque the anti-seize acts as a lubricant and you will be over torqueing the plug and my strip the threads out of the head.
 

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Discussion Starter #6
They used the copper plugs because replacing them at 30,000 miles made it easer and safer getting the steel plugs out of an aluminum head. they did not want to have the problems Ford has with the plugs braking or pulling the threads out of the head after sitting unmoved for all the years it took to go a 100,000 miles. And with 16 plugs there is twice the chances of that happening. It is important to change them on time as the plug wears the gap gets larger you don't have any signs like ruff running or poor performance because the ECU increases the burn time on the coils to jump the wider gap of the plugs witch will make your coils wear out much sooner then they should. Also the plugs should be put in dry if anti-seize is used and you use a torque wrench to put then in at the proper torque the anti-seize acts as a lubricant and you will be over torqueing the plug and my strip the threads out of the head.
Great info. I think I got it. Use OEM Copper. No anti-seize. Torque to 13 ft-lbs. Gap - .043. Need 16, not 8.

Any tricks on getting them out (Factory originals at 65K on a 2013). Went into service in November 2012.....so, I'll be well over 5 years when I attempt this in the spring.

Any more "and don't ever ever .........." tips?
 

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At 5 years they my be a little harder to get out but the real danger is ones that have been in for 7 or 8 years. Go slow taking them out it helps that if they feel like they are getting harder to turn as they are coming out reverse the ratchet and turn them back in a little that can help clear the threads of the carbon build up and make them come out with out damaging the heads. Its like running a thread chaser in to a threaded hole and running it in a little then back out some to clear the shavings out if you just run it in and use fore force when it gets tight you may break the tap off in the hole.
 

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The type of material (i.e. copper...iridium...platinum) describes the electrode not what the threads are made of. All plugs run the same risk of damaging an aluminum head as the plug thread is made from steel which is usually plated.

https://www.carsdirect.com/car-repair/copper-spark-plugs-vs-iridium-and-platinum-understand-for-top-performance

As for changing the plugs. It usually takes me around an hour on the challenger and a little longer on my GC:

1) unplug the coil packs
2) unscrew coil pack bolts (careful not to completely unscrew from the coil pack but just the valve cover)
3) remove coli packs (inspect the boots for oil as it will indicate if your valve cover seal is bad)
4) unscrew and remove spark plugs (I put them in the boxes of the new plugs and label them so I can inspect later)
5) apply anti-seize to new plugs (hand thread all the way and torque per manual)
6) install coil packs (I don't keep track of which cylinder they came from)
7) torque the coil pack bolts
8) reattach the connectors to the coil packs (you can't screw this up as the connectors won't reach other cylinders)
 

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Discussion Starter #9
What's the torque rating on the coil pack bolts?

First warm day in March, I'll take the cover off, take 'er down off the blocks, pull into the garage, and give this a go.
 

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They used the copper plugs because replacing them at 30,000 miles made it easer and safer getting the steel plugs out of an aluminum head. they did not want to have the problems Ford has with the plugs braking or pulling the threads out of the head after sitting unmoved for all the years it took to go a 100,000 miles. And with 16 plugs there is twice the chances of that happening. It is important to change them on time as the plug wears the gap gets larger you don't have any signs like ruff running or poor performance because the ECU increases the burn time on the coils to jump the wider gap of the plugs witch will make your coils wear out much sooner then they should. Also the plugs should be put in dry if anti-seize is used and you use a torque wrench to put then in at the proper torque the anti-seize acts as a lubricant and you will be over torqueing the plug and my strip the threads out of the head.
You probably won't have any issues - it took me 6 years to get to the 30K interval and they came out fine.

The only plugs that are a little more work is cyl #2 since the 5.7 dipstick is near that set - you just have to nudge it out of the way...or loose the nut that holds the dipstick down (near exhaust) and you can rotate the tube out of the way.

Probably for cost / maintenance reasons the 5.7s had copper core plugs /30K intervals. The '14s went to platinum, but those are more expensive. If you want to go with the them the Iridium plugs will fit.

NGK is the OEM plug used. I'd stick with them - Chrysler spec'd particular heat ranges for their plugs and NGK did an application for their spec.
 

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Discussion Starter #12
Is it acceptable to put the iridium plugs in when the car had copper from the factory? IF so, why didn't they just put iridium plugs in, in the first place. And if I do put them in, are they then 100K plugs from that point? Or still every 30K.

I'm going to replace my original copper plugs at 65K in the next few weeks, and, by gum, if I can put iridium plugs in, I'll never have to change them again (I'll have long traded this one in).
 

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Is it acceptable to put the iridium plugs in when the car had copper from the factory? IF so, why didn't they just put iridium plugs in, in the first place. And if I do put them in, are they then 100K plugs from that point? Or still every 30K.

I'm going to replace my original copper plugs at 65K in the next few weeks, and, by gum, if I can put iridium plugs in, I'll never have to change them again (I'll have long traded this one in).
Look up the spec that a '14 R/T has - the 5.7s used iridium plugs from that year forward. They are the same reach / thread / heat range as the '09 - '13 5.7s
-NGK is the OEM brand of plug used by Chrysler.
 

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"Copper spark plugs" is a term mistakenly used for a standard material spark plug. A standard material spark plug traditionally uses a nickel-alloy outer material fused to a copper core. "Almost all spark plugs use a copper core center to conduct the electricity, jump the gap, and promote heat dissipation." However, as an outer electrode material, copper would not be a good choice, as it is soft and has a low melting point (resulting in a plug that would last minutes, not miles). Nearly all spark plugs, including precious metals iridium and platinum, have a copper core. When one talks in terms of nickel alloys, platinum and iridium, one is referring to its durability, or how long a spark plug will last before it needs to be replaced. "However, when one talks about copper, he or she is referring to its ability to conduct electricity that is needed to fire across the gap and ignite the air-fuel mixture."
I would like to know where the term "copper spark plugs" came from because it causes alot of misinformation.
 

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Discussion Starter #15
"Copper spark plugs" is a term mistakenly used for a standard material spark plug. A standard material spark plug traditionally uses a nickel-alloy outer material fused to a copper core. "Almost all spark plugs use a copper core center to conduct the electricity, jump the gap, and promote heat dissipation." However, as an outer electrode material, copper would not be a good choice, as it is soft and has a low melting point (resulting in a plug that would last minutes, not miles). Nearly all spark plugs, including precious metals iridium and platinum, have a copper core. When one talks in terms of nickel alloys, platinum and iridium, one is referring to its durability, or how long a spark plug will last before it needs to be replaced. "However, when one talks about copper, he or she is referring to its ability to conduct electricity that is needed to fire across the gap and ignite the air-fuel mixture."
I would like to know where the term "copper spark plugs" came from because it causes alot of misinformation.
Maybe it's the material that the electrode is made of, the place where the spark jumps the gap. This is where the most "wear" would occur, so is the "Copper, Iridium, Platinum" reference to the material at this wear point?
 

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Discussion Starter #17
Great information from Advance Auto Parts (my son-in-law manages a store, so I get the family discount).

Here's the part on Copper Plugs that applies to my 2013 R/T Classic.

Copper spark plugs are best for older (pre-‘80s) vehicles with low voltage distributor-based ignition systems. Don’t use copper spark plugs in high-energy distributor-less ignition systems (DIS) or coil-on-plug (COP) ignition systems. They’ll wear out too quickly.

There’s one exception to that advice. Some late-model high-performance engines were designed specifically for copper spark plugs. In those cases, copper spark plugs are considered to be high performance spark plugs. If your owner’s manual calls for copper spark plugs, don’t upgrade to platinum spark plugs or iridium spark plugs.
 

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Great information from Advance Auto Parts (my son-in-law manages a store, so I get the family discount).

Here's the part on Copper Plugs that applies to my 2013 R/T Classic.

Copper spark plugs are best for older (pre-‘80s) vehicles with low voltage distributor-based ignition systems. Don’t use copper spark plugs in high-energy distributor-less ignition systems (DIS) or coil-on-plug (COP) ignition systems. They’ll wear out too quickly.

There’s one exception to that advice. Some late-model high-performance engines were designed specifically for copper spark plugs. In those cases, copper spark plugs are considered to be high performance spark plugs. If your owner’s manual calls for copper spark plugs, don’t upgrade to platinum spark plugs or iridium spark plugs.
FCA probably went for convention plugs on 5.7s for cost purposes. With the majority of new vehicles having longer change intervals (just like your post asking why only 30K intervals) - they finally moved over to the 100k iridium tip plug as FCA uses on 3.6 V6, 6.1 SRT, 392 SRT engines all along.

A few dollars per engine over thousands of them adds to production costs. To be competitive (lower cost of maintenance over service life) they matched what other makes are doing.

The coil packs on a '13 and earlier are the same ones used on 14+ 5.7s
 

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Discussion Starter #19
FCA probably went for convention plugs on 5.7s for cost purposes. With the majority of new vehicles having longer change intervals (just like your post asking why only 30K intervals) - they finally moved over to the 100k iridium tip plug as FCA uses on 3.6 V6, 6.1 SRT, 392 SRT engines all along.

A few dollars per engine over thousands of them adds to production costs. To be competitive (lower cost of maintenance over service life) they matched what other makes are doing.

The coil packs on a '13 and earlier are the same ones used on 14+ 5.7s
So that sounds to me like there's no reason why I shouldn't put the longer lasting iridium ones in. Same coil packs, same block, heads, all engine parts where the "Bang" happens.....I'd rather spend a few buck and not do this for another 100K. Will be somebody else's car by then anyway. But I'll definitely have it for another 30K.
 

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Maybe it's the material that the electrode is made of, the place where the spark jumps the gap. This is where the most "wear" would occur, so is the "Copper, Iridium, Platinum" reference to the material at this wear point?
No. Almost ALL spark plugs have a copper core inside the body and in the ground electrode. None have exposed copper anywhere.

"However, as an outer electrode material, copper would not be a good choice, as it is soft and has a low melting point (resulting in a plug that would last minutes, not miles). Nearly all spark plugs, including precious metals iridium and platinum, have a copper core.
 
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