I replaced all 16 plugs yesterday as part of doing maintenance on my neglected 2013 Dodge Charger 5.7 Hemi. The car was parked for about 3 years prior to my purchasing it last year. The PO did nothing to this car except oil changes. It had the original plugs, coolant, air filter, transmission filter and fluid, axle fluid, no ps fluid. Attached are pics of the original NGK LZFR5C11 plugs I pulled out at 74k. These are copper plugs and are scheduled to be changed every 30k.
Spark plug replacement 2013 Hemi 5.7
- Thread starter Bailey28
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Copper plugs on that new of a car? I thought all modern cars take either platinum or iridium where the center electrode is real skinny.
Looks like an octane booster was used some and you have some oil consumption in one cylinder.
Guy down the street has one that must be straight piped...I've never seen anything that slow be that loud.
Guy down the street has one that must be straight piped...I've never seen anything that slow be that loud.
OVERKILL
$100 Site Donor 2021
You must not remember the 305 powered Camaros with glass packs on them, lol.
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They're all doing that now. It's rare these days to find a modern muscle car with ear friendly factory exhaust.
I would hardly classify 4300Lbs/automatic/375 HP as a "Muscle car"...but that didn't stop him from doing it.
Yes, NGK's from the factory for HEMI's.
Gotta pinch them pennies. 2013~2014 they transitioned them all to iridium plugs.... The "police package" up to that point got iridium's from the factory.
And yet my 2014 Challenger R/T mops the floor with my brothers '66 Charger in a race
What engine in the '66 Charger? 383?Yes, NGK's from the factory for HEMI's.
Gotta pinch them pennies. 2013~2014 they transitioned them all to iridium plugs.... The "police package" up to that point got iridium's from the factory.
And yet my 2014 Challenger R/T mops the floor with my brothers '66 Charger in a race
So, they're $5 each on Rock Auto, which seems like a lot for nickel "copper" plugs (even other NGK OE plugs of that type are usually under $3 each), and that adds up when you have 16 
There's also a note under it saying that FCA/Stellantis now recommends iridium. The NGK iridium is $7 each but should be good for at least 100k. Denso offers both Platinum and Iridium TT for the Hemi, which are good for 60k and 100k, respectively.
The NGK G-Power is slightly less money than OE and is single platinum (should be good for 60k if those are good for 30k)
There's also a note under it saying that FCA/Stellantis now recommends iridium. The NGK iridium is $7 each but should be good for at least 100k. Denso offers both Platinum and Iridium TT for the Hemi, which are good for 60k and 100k, respectively.
The NGK G-Power is slightly less money than OE and is single platinum (should be good for 60k if those are good for 30k)
OVERKILL
$100 Site Donor 2021
I mean, it's a mid to low 14 second car, which is actually very competitive with many of the muscle cars from the 60's and 70's and faster than a good portion of them. My Jeep will run high 12's, but the ZF8HP is a better transmission and the 392 makes a fair bit more power.
I replaced them with Champion copper 446 (REC12MCC4) plugs. Pre gapped to .044". If anyone knows how to read NGK plug date codes I can post to see when they were made. I do strongly believe they are the originals. PO did nothing to the car.
In 2014 Dodge changed plugs to the Iridium and moved replacement to 100k in civilian Hemi engines.
The car runs much better with the new plugs. The PO did fill the tank and put Stabil in so maybe that is the deposit formation on the plugs. Two of the plugs that are dark came from #3 on the driver side. I have refilled the tank a few times since I have been driving it more as of Januray.
I found a box of 24 Champion plugs new shipped for $33 total, for $1.37/plug. I have 8 leftovers now lol. Buying 16 with shipping from RA was more than $33.
In 2014 Dodge changed plugs to the Iridium and moved replacement to 100k in civilian Hemi engines.
The car runs much better with the new plugs. The PO did fill the tank and put Stabil in so maybe that is the deposit formation on the plugs. Two of the plugs that are dark came from #3 on the driver side. I have refilled the tank a few times since I have been driving it more as of Januray.
I found a box of 24 Champion plugs new shipped for $33 total, for $1.37/plug. I have 8 leftovers now lol. Buying 16 with shipping from RA was more than $33.
From where?
Someone swapped in a 440 prior to him owning it.
I also think the plugs that appear darker were from the cylinders that are deactivated with MDS. As good as piston ring technology is I would venture to guess some oil still makes it past the ring pack and might cause extra deposits in those temporarily deactivated cylinders over time. The engine calls for 5w-20 oil. The Hemi disables cylinders 1 4 6 and 7.
