NGK · New

NGK Iridium IX Spark Plug Box of 4 (LTR6IX-11)

Name: NGK Iridium IX Spark Plug Box of 4 (LTR6IX-11)
Brand: NGK
SKU: ngk6509
Price: 90.60 USD

MPN 6509 · Store SKU ngk6509

$90.60

CHECK AVAILABILITY0 in supplier warehouses. Ask JuiceBuilt about availability.

Supplier stock checked 11/7/2026, 4:35:30 AM UTC. Adding a part does not reserve it.

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Request a return within 30 calendar days after delivery. New parts must be unopened and unused.

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Free standard shipping on eligible parts orders of $100 or more. Oversized and freight items excluded. Fitment, taxes, availability and final totals are confirmed before payment.

Product details

NGK Iridium IX spark plugs are specifically designed for the performance enthusiast. Iridium IX provides outstanding acceleration, high fuel efficiency and durability. NGK Iridium IX plugs offer extreme ignitability and exceptional anti-fouling. Tapered cut ground electrode provides improved starting, idling and throttle response. The Iridium fine wire center electrode's durability is six times harder than platinum. Iridium alloy's extremely high melting point is perfect for today's engines. For even greater performance consider upgrading to an NGK Ruthenium HX plug. The improved throttle response, superior anti-fouling and high-ignitability makes Iridium IX® the ideal choice for any performance enthusiast. Iridium's high melting point is perfectly suited to today's high-temperature engines, delivering outstanding acceleration, fuel efficiency and durability. NGK Iridium IX spark plugs are specifically designed for the performance enthusiast. Iridium IX provides outstanding acceleration, high fuel efficiency and durability. NGK Iridium IX Spark Plug

Manufacturer fitment & guides

BUICK 2017-05; CADILLAC 2017-04; CHEV 2017-08; FORD 2017-10; GMC 2017-07; MAZDA 2015-07; PONT 2009-07; SAAB 2011; SATURN 2009-07; SUZ 2010-07

Manufacturer-supplied application summary from Turn14; this may not be an exhaustive fitment list.

A manufacturer application guide is not available for this listing. Request the exact application from JuiceBuilt before payment.

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What is the return policy?

Request a return within 30 calendar days after delivery. New parts must be unopened and unused.

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This policy does not limit rights required by law.

NGK Iridium IX Spark Plug Box of 4 (LTR6IX-11)

Product details

Manufacturer fitment & guides

THE NEXT PART
OF YOUR BUILD.

Free shipping on $100+ orders.

Build with the right brands.

Find your next upgrade.

Make the whole setup work.

A few things to know.

Your build.

Delivery & checkout

Delivery address