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Iridium sparkplugs?

Are they worth the extra cost?


  • edited April 2011
    If there's easy access to the spark plugs they're not worth the money. These exotic metals are used on spark plugs are for longer life of the spark plug. So if access to the spark plugs is hard you use these type of spark plugs. Otherwise, platinum plugs are good enough.

  • edited April 2011
    Yes. They're Factory Issue In My Bonneville And They Work Well And Last A Long, Long Time. If That's The Original Equipment Plug Then Put Them Back In There. Otherwise Use What Was Specified Originally.

  • edited April 2011
    If you are looking for improved performance or better fuel economy, you will not get it by paying extra for exotic spark plugs. If your spark plugs are really buried and you don't ever want to have to replace them again, they might just be worth it. Platinum plugs are plenty sufficient for most people. I have replaced platinum plugs that had over 100k miles on them and they still looked like new. I say for your Silverado 1500, use whatever the factory specified, even if it calls for copper core. I can't think of a single Silverado with difficult to change spark plugs.
  • edited April 2011
    Use whatever was in the car. I just replaced mine at 68K and they hardly looked worn at all. I expect either I or the car will be dead before I have to do it again. One thing though is don't set the gap. They come factory set and they are too brittle to mess with the gap.
  • edited April 2011

    Unfortunately many manufacturers are now making them standard. For my wifes Lexus...Iridium are the only plugs available...And as of last year...Denso was the only manufacturer.
  • edited April 2011
    Put In The Plugs That The Manufacturer Specifies. As I Said Earlier, My Bonneville Specs AC Delco #41-101 Iridium Spark Plugs. I Paid 6 Bucks Each For Them At Advance Auto Last Fall, Not A Big Deal Every 100,000 Miles.

    After 100,000 miles the business end of the plugs still look new.

  • edited April 2011
    Iridium does not react with Nitros used for street racing. Platinum does react to nitros and they get ruined. Iridium is not needed and costs way more than standard plugs. Buy the ones that came with the truck and save your money.
  • edited April 2011
    I am the tech manager at Autolite spark plugs. Alot of misconceptions about iridium spark plugs on this forum. Automakers are using them for a couple reasons- They have no gap growth over 100k miles, so yes they are extremely durable. They are benefits to using them in any car. They use less voltage to fire, amek a larger flame kernal in the combustion chamber and actuall burn more of the fuel that goes through the engine.All real benefits based on technology, not gimmicks. Believe me, automakers never want to pay more for any part, when they do it is because there is a real performance benefit.
  • edited April 2011
    Autolite has iridium spark plugs for your lexus.
  • edited April 2011
    They have no gap growth over 100k miles, so yes they are extremely durable.

    Have you ever tried removing a spark-plug that's been in an engine for 100k miles??? I've done it once and won't do it again...Of the 6 plugs removed...two had to be helicoiled (especially dangerous with aluminum heads).

    A lower voltage and higher flame does NOT mean better performance or better gas-mileage.....nor does it mean it'll burn more fuel.
    Believe me, automakers never want to pay more for any part, when they do it is because there is a real performance benefit.

    The MAIN reason is because of longevity...PERIOD...Performance - Marginal at best.

    As for Auto-lite plugs...While I never had a problem with Fram filters...I've had MAJOR problems with Auto-lite plugs....They are by most people I know to be the low-end of the low-end plugs. If you want the cheapest plugs available and don't car about your Auto-lite...The difference between Auto-lite plugs and NGK is about the same as a Rolls Royce and a Pinto.
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