Jeep Garage  - Jeep Forum banner

1 - 6 of 6 Posts

·
Registered
Joined
·
443 Posts
Discussion Starter #1
I've read several of the older posts about who uses what for their spark plugs. I'm going to have some free time over the holiday (and may need to get away from all the family in town periodically) and was going to change the plugs in my '15 Hemi. Only at 42,000 miles but I figure why not. What have you all found to be the best replacement for the OE spark plug? Bosch Irridium? NGK Laser Irridium? Both available from my local Advance Auto Parts (professional courtesy they give me a 30% discount). Thanks. Happy Thanksgiving
 

·
Premium Member
Trailhawk
Joined
·
975 Posts
I'm a little biased and love the Champion 9055 Iridiums. 100,000 mile plugs and their metal threads and shells are treated with a product to keep them from corroding or rusting. Rock Auto has them for $4.61.
 

·
Premium Member
Trailhawk
Joined
·
975 Posts

Scroll down to specifications for further info.
 

·
Registered
GC TH
Joined
·
403 Posts
I’d stick with OEM NGK. Not made in China and more reliable than a lot of others. I think you’re changing them early (depending on driving style/towing, etc), but I agree that no one should actually wait 100k miles to change them.

From wk2jeeps:

5.7 V8 Hemi (2011-2013)
Mopar p/n 05149177AB (NGK Yttrium ZFR5C-11)
(.043 gap, 16 plugs, tighten to 13 ft. lbs. (+/-2) (18 N·m, +/-3).
(Torque critical tapered design. Do not exceed 15 ft. lbs.)

5.7 V8 Hemi (2014-up)
Mopar p/n SP143877AB (NGK Iridium LZFR5CI-11, NGK Stock Number 92145)
(.043 gap, 16 plugs, tighten to 18-21.6 ft. lbs. (+/-2) (24-28 N·m, +/-3).
 

·
Registered
Grand Cherokee
Joined
·
3,349 Posts
First, spark plugs aren't going to get you extra power... ....lots of companies will claim it, they may even cite tests they've done, were they replaced worn out plugs with their new plugs and measured a 15hp gain, what they don't tell you, if they had replaced worn out plugs with the OEM or any new plug, they would have gained back the same 15hp, that was loss gradually as the plugs wore out.....

Racing catalogs are full of ignition equipment for two reasons, race catalogs also sell useless gimmicks to make a buck, there are people that actually race and build highly modified motors making twice the stock power or go to 3k rpm higher than stock, when you get into this territory, you may need better ignition than stock.... ...you've got bolts on an extra 20-50hp, extra ignition isn't getting you anything....

Some people report problems with anything other than the OEM plugs with modern engines....
Perhaps the ignition systems are more finicky than the past, or the aluminum head, emissions, etc make exact ignition more critical....

There are also different modern ignition schemes, liked shared coil, wasted spark that reverse current direction on half the plugs, that can't work with single platinum plugs... ...you need double platinum, they may work, but half you plugs will wear out very quickly....

I also think people are not checking the gap on their plugs before they install them, even pre-gapped plugs may not be gapped properly for you particular engine....

So the conventional wisdom is just use the OEM Plug, avoid any of the hassles other folks have experienced....

HEMI's used to have Champion Copper Plugs, they switch suppliers to NGK.... ....seen lots of posts that folks get good results with Champion from the older HEMI, but probably the same result as if they had used the OEM NGK....

Seen lots of posts that people tried the later NGK Iridium Lazer plugs in the earlier HEMI's and never had a problem... ...I've switched to the NGK Iridium Lazer plugs for the 2014 and on HEMI in my 2011 HEMI and they run exactly the same, I just don't have to worry about them for 100k miles.....

Lots of posts that people have gone twice the change interval on the copper plugs for the HEMI and suffered no symptoms of worn plugs.... ....when I changed the copper plugs on my 2011 HEMI at the recommended 32k miles, the old plugs looked like they only had a thousand miles on them, the gap was the exact same as new as well.... ...so it appears the HEMI is easy on its plugs and they last longer the standard 33k mi change interval for copper plugs...
 
1 - 6 of 6 Posts
Top