I put 200K miles on my original plugs on my [99] 4.6 Marquis..My [05] 4.6 Vic has 125K miles on the plugs right now.
longest lasting spark plugs?
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Originally Posted By: dparm
Iridium will be the slowest to degrade in most applications.
I think it's silly to say that "NGKs last longer" than some other brand.
Well, I don't think it's silly to say that NGKs last a LOT longer than Bosch spark plugs.
Iridium will be the slowest to degrade in most applications.
I think it's silly to say that "NGKs last longer" than some other brand.
Well, I don't think it's silly to say that NGKs last a LOT longer than Bosch spark plugs.
Originally Posted By: hattaresguy
With a modern motor I almost wouldn't bother changing the plugs anymore.
I changed the AC Delco original plugs in my Silverado last fall at 85k and they looked perfect. I don't plan on ever changing them again.
I'd just run them until one fails, and I bet that's north of 200k.
Agree.
When I had original Bosch plugs in my E430 replaced 4-5 years ago at 8x,xxx miles they looked perfect too. Since I didn't have the tools and knowledge/skill to do it myself, I had the car at my local garage and already bought 16 plugs for replacement, I just had it changed. If I the the tools I would remove 1 or 2 plugs and after seeing the condition I would reuse it without worrying.
Originally Posted By: L_Sludger
Originally Posted By: dparm
Iridium will be the slowest to degrade in most applications.
I think it's silly to say that "NGKs last longer" than some other brand.
Well, I don't think it's silly to say that NGKs last a LOT longer than Bosch spark plugs.
May be in non-European engines. Bosch plugs lasted very long in European engines, specially German engines.
With a modern motor I almost wouldn't bother changing the plugs anymore.
I changed the AC Delco original plugs in my Silverado last fall at 85k and they looked perfect. I don't plan on ever changing them again.
I'd just run them until one fails, and I bet that's north of 200k.
Agree.
When I had original Bosch plugs in my E430 replaced 4-5 years ago at 8x,xxx miles they looked perfect too. Since I didn't have the tools and knowledge/skill to do it myself, I had the car at my local garage and already bought 16 plugs for replacement, I just had it changed. If I the the tools I would remove 1 or 2 plugs and after seeing the condition I would reuse it without worrying.
Originally Posted By: L_Sludger
Originally Posted By: dparm
Iridium will be the slowest to degrade in most applications.
I think it's silly to say that "NGKs last longer" than some other brand.
Well, I don't think it's silly to say that NGKs last a LOT longer than Bosch spark plugs.
May be in non-European engines. Bosch plugs lasted very long in European engines, specially German engines.
Plug life is probably impacted by the application as much as it is the brand of the plug. My truck came from the factory with 100K mile plats, but when I changed them at 80K the electrodes were pretty worn. They would have made it to 100K, but performance would have degraded as the gaps were way off. This truck has run on ethanol for probably 50% of its life though, so that may have been harder on the plugs. Aside from the worn electrodes, they looked great.
I will agree that you can't go wrong with NGK plugs though. Their quality is top notch.
I will agree that you can't go wrong with NGK plugs though. Their quality is top notch.
Originally Posted By: hattaresguy
I'd just run them until one fails, and I bet that's north of 200k.
I guess that's why they call it "preventative" maintenance
hehehe. But yea.....I'm kind of thinking the same thing....changing out mine though this coming week (waiting on the plugs and wires from RockAuto hehe).
I'd just run them until one fails, and I bet that's north of 200k.
I guess that's why they call it "preventative" maintenance
I just changed out the plugs in another vehicle. She had 108k on the NGK Iridium and they looked pretty good for the miles on them.
I put new plugs of the same.
I put new plugs of the same.
Originally Posted By: hisilver
Originally Posted By: dailydriver
Originally Posted By: dparm
Iridium will be the slowest to degrade in most applications.
I think it's silly to say that "NGKs last longer" than some other brand.
Denso does not make a VERY high mileage Iridium plug like NGK's Laser.
Last I checked they only made the higher performance, 0.4 diameter center electrode deal which supposedly only lasts for ~ 30K miles (at least that's when Denso suggests they be changed out).
Denso makes two Iridium plugs, the Iridium Power (for high performance cars) and Iridium Long Life (for 100k miles lifespan). The Iridium Power plugs are scheduled to be replaced much under 100k miles, something like 30K IIRC.
Yes, you are correct (I forgot about their long life Iridiums!
).
Denso Iridium Power =~ NGK Iridium IX (although some claim that the Denso is better because of the smaller diameter center electrode
)
Denso Iridium Long Life =~ NGK Laser Iridium
Originally Posted By: dailydriver
Originally Posted By: dparm
Iridium will be the slowest to degrade in most applications.
I think it's silly to say that "NGKs last longer" than some other brand.
Denso does not make a VERY high mileage Iridium plug like NGK's Laser.
Last I checked they only made the higher performance, 0.4 diameter center electrode deal which supposedly only lasts for ~ 30K miles (at least that's when Denso suggests they be changed out).
Denso makes two Iridium plugs, the Iridium Power (for high performance cars) and Iridium Long Life (for 100k miles lifespan). The Iridium Power plugs are scheduled to be replaced much under 100k miles, something like 30K IIRC.
Yes, you are correct (I forgot about their long life Iridiums!
Denso Iridium Power =~ NGK Iridium IX (although some claim that the Denso is better because of the smaller diameter center electrode
Denso Iridium Long Life =~ NGK Laser Iridium
Originally Posted By: HTSS_TR
Originally Posted By: hattaresguy
With a modern motor I almost wouldn't bother changing the plugs anymore.
I changed the AC Delco original plugs in my Silverado last fall at 85k and they looked perfect. I don't plan on ever changing them again.
I'd just run them until one fails, and I bet that's north of 200k.
Agree.
When I had original Bosch plugs in my E430 replaced 4-5 years ago at 8x,xxx miles they looked perfect too. Since I didn't have the tools and knowledge/skill to do it myself, I had the car at my local garage and already bought 16 plugs for replacement, I just had it changed. If I the the tools I would remove 1 or 2 plugs and after seeing the condition I would reuse it without worrying.
Originally Posted By: L_Sludger
Originally Posted By: dparm
Iridium will be the slowest to degrade in most applications.
I think it's silly to say that "NGKs last longer" than some other brand.
Well, I don't think it's silly to say that NGKs last a LOT longer than Bosch spark plugs.
May be in non-European engines. Bosch plugs lasted very long in European engines, specially German engines.
I should have put a caveat in my statement.
In engines like your M113 that have aluminum heads and nice long plug threads I would change the plugs every 4-5 years for the simple reason that I don't feel like helicoiling the threads when they come out with the plug after 10.
In old school engines like the 4.3 in my truck with iron heads its not a problem, just put a wrench on the plug and force it out.
Originally Posted By: hattaresguy
With a modern motor I almost wouldn't bother changing the plugs anymore.
I changed the AC Delco original plugs in my Silverado last fall at 85k and they looked perfect. I don't plan on ever changing them again.
I'd just run them until one fails, and I bet that's north of 200k.
Agree.
When I had original Bosch plugs in my E430 replaced 4-5 years ago at 8x,xxx miles they looked perfect too. Since I didn't have the tools and knowledge/skill to do it myself, I had the car at my local garage and already bought 16 plugs for replacement, I just had it changed. If I the the tools I would remove 1 or 2 plugs and after seeing the condition I would reuse it without worrying.
Originally Posted By: L_Sludger
Originally Posted By: dparm
Iridium will be the slowest to degrade in most applications.
I think it's silly to say that "NGKs last longer" than some other brand.
Well, I don't think it's silly to say that NGKs last a LOT longer than Bosch spark plugs.
May be in non-European engines. Bosch plugs lasted very long in European engines, specially German engines.
I should have put a caveat in my statement.
In engines like your M113 that have aluminum heads and nice long plug threads I would change the plugs every 4-5 years for the simple reason that I don't feel like helicoiling the threads when they come out with the plug after 10.
In old school engines like the 4.3 in my truck with iron heads its not a problem, just put a wrench on the plug and force it out.
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I put Autolite Iridiums in my 2009 5.7 Hemi. I called several plug manufactures and talked to their product assistance techs. Autolite was the most pleasant and helpful person I talked to. Their plugs built as good as anyone's with a 5 year guarantee regardless of miles. I found them on sale at Amazon.com for around $6 bucks each. Then Autolite had a $2 buck each rebate on them.Truck runs good and may have a bit of a smoother idle.
^^^Good call. Newer Hemis run great on any kind of plug. I always tell my friends to choose your plug by how often you want to fool with them.
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