How do I find the right spark plug for my vehicle?

Use your vehicle's Year, Make, and Model along with engine size to find the correct plug. Every product listing includes compatibility information. If you're unsure, your vehicle's owner's manual will list the OEM spark plug part number, which you can use to cross-reference our catalog. You can also contact us at Contact Us and we'll help you find the right part.

What's the difference between copper, platinum, and iridium spark plugs?

Copper: Best conductivity, lowest cost, shortest lifespan (~20,000–30,000 miles). Good for older vehicles or high-performance builds with frequent tune-ups. Platinum: Harder electrode, lasts ~60,000 miles. Standard upgrade for most modern vehicles. Iridium: Hardest material, finest electrode tip, best ignitability, longest life (~80,000–100,000+ miles). Best choice for most modern engines.

Can I use aftermarket spark plugs instead of OEM?

Yes — in most cases, quality aftermarket plugs from NGK, Champion, ACDelco, or Autolite perform equal to or better than OEM. These brands supply original equipment to major automakers. Always match the heat range and electrode type recommended for your engine.

How often should I change my spark plugs?

Copper plugs: every 20,000–30,000 miles. Platinum plugs: every 60,000 miles. Iridium plugs: every 80,000–100,000 miles. Check your owner's manual for your vehicle's specific interval. Symptoms of worn plugs include rough idle, misfires, reduced fuel economy, and hard starting.

Do you offer free shipping?

Yes — all orders ship free , with no minimum purchase required. Free shipping applies to every order, every time.

How long does shipping take?

Orders are processed within 1–2 business days. Standard delivery typically takes 3–7 business days after processing. You will receive a tracking number by email once your order ships.

Do you ship internationally?

At this time we ship within the United States only.

What if I received the wrong item or a defective part?

Contact us immediately at Contact Us with your order number and a photo of the item. We will ship a replacement or issue a full refund at no additional cost to you.

What brands do you carry?

We carry the industry's most trusted brands: NGK, Champion, ACDelco, Motorcraft, Autolite, Permatex, Lucas Oil, and ATP . Our catalog includes 19,000+ parts covering spark plugs, iridium plugs, oil filters, air filters, oxygen sensors, automotive chemicals, and more.

Are your parts new or remanufactured?

All parts we sell are new — never remanufactured, rebuilt, or used. Every product ships from the original manufacturer's current production run.

How do I know a part will fit my vehicle before I buy?

Each product listing includes vehicle compatibility details. If you have any doubts, email us at Contact Us before ordering. We'd rather confirm fitment upfront than process a return later.

How do I reach customer support?

Email: Contact Us Phone: 512.850.6844 Address: 121 Spur 191, PO Box #242, Spicewood, TX 78669 We respond to all inquiries within 1 business day.

Home / 1 Pack Denso 5364 Iridium Power Spark Plug IU31

1 Pack Denso 5364 Iridium Power Spark Plug IU31

Name: 1 Pack Denso 5364 Iridium Power Spark Plug IU31
Brand: TXN Supply Co
SKU: DEN-5364-1PK-EB
Price: 32.77 USD
Availability: OutOfStock

$32.77

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1 Pack Denso 5364 Iridium Power Spark Plug IU31

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Product Description

The Denso 5364 Iridium Power Spark Plug (IU31) is engineered for high-demand engines that require a colder heat range and maximum spark efficiency. Designed with a fine-wire iridium center electrode and a compact 10mm thread size, it delivers fast starts, improved throttle response, and reliable combustion in motorcycles, ATVs, and performance machines.

Features & Benefits:

🔧 Iridium tip provides long-lasting spark performance
🔧 Cold heat range ideal for tuned or high-load engines
🔧 Compact thread design suits motorcycles and powersports
🔧 Pre-gapped to manufacturer specs for easy fitment

Specifications:

Brand & Part Number: Denso 5364 (IU31)
Material: Iridium
Thread Size: 10mm
Reach: 19mm (0.75 in)
Hex Size: 16mm
Heat Range: 31
Seat Type: Gasket
Resistor: Yes
Gap: 0.6mm (0.024 in)

Count on Denso Iridium Power IU31 for extreme reliability and consistent ignition in every ride—upgrade today!

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At TXN Supply, we're driven by a passion for quality and reliability. Whether you're a DIY mechanic, an automotive professional, or just looking for top-notch essentials, we provide premium spark plugs, oil filters, fluids, and more from trusted brands like Champion, NGK, and ACDelco.

Our mission is simple: to deliver high-quality auto parts and everyday must-haves with fast shipping and great prices!

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