OVERSTOCKDIRECT Iridium Spark Plugs 6-Pack SP580X (CYFS12YT4X) — OEM fit, long-life ignition

OVERSTOCKDIRECT SP580X (CYFS12YT4X) is a six-pack of genuine OEM iridium spark plugs designed as a direct replacement for SP580/CYFS12YT4 applications, now shipped in the updated SP580X version.

These spark plugs are sold as an OEM-quality replacement kit for compatible engines and provide long-lasting ignition performance thanks to an iridium center electrode. Before ordering, verify the plug part number and vehicle compatibility—engine type, drivetrain and trim level can affect the correct fit. This listing contains six spark plugs (suitable for six-cylinder applications or to keep a spare set) and represents the updated SP580X revision of the original SP580/CYFS12YT4 design.

How do these iridium plugs differ from standard plugs?

Iridium is a harder, higher-melting-point metal than conventional nickel used for electrodes, enabling a finer tip that delivers a more consistent spark and improved wear resistance. That precision can help maintain reliable ignition timing and reduce electrode erosion over time without changing the engine’s factory settings.

• Iridium center electrode for stable spark and extended service life
• Fine-tipped design improves ignition consistency
• OEM specification ensures correct heat range and reach

Will these SP580X plugs fit my vehicle?

Compatibility depends on your vehicle’s exact engine code, model year and equipment level. The part number SP580X (CYFS12YT4X) replaces the older SP580 (CYFS12YT4) — but you should compare the part numbers with your vehicle’s service manual or parts lookup to confirm fitment.

• Check OEM part number: SP580X / CYFS12YT4X
• Confirm engine, drivetrain and trim specifics before purchase
• Suitable as a full six-plug set for applicable engines

What maintenance benefits can I expect from using OEM iridium plugs?

Using OEM-spec iridium plugs helps preserve factory performance characteristics and reduces the frequency of replacements compared with standard plugs. Because they adhere to original equipment tolerances, they minimize the risk of misfire or calibration issues that can arise from incorrect aftermarket substitutes.

• Longer service intervals versus conventional plugs
• Consistent factory-calibrated performance and reliability
• Reduced electrode wear helps sustain ignition quality

How should I install and care for these spark plugs?

Install following the vehicle manufacturer’s torque and gap specifications; do not overtighten. Use a calibrated torque wrench and anti-seize only if your vehicle manual specifies it. Regular visual inspections during scheduled maintenance will reveal electrode wear or fouling.

• Torque to manufacturer-specified value; verify spark gap if required
• Replace all plugs in a bank for consistent ignition behavior
• Follow vehicle service intervals for inspection and replacement

Who is this for? These OVERSTOCKDIRECT SP580X (CYFS12YT4X) iridium spark plugs are aimed at drivers and mechanics who want OEM-level replacement parts for compatible vehicles, especially those seeking longer-lasting ignition components for six-cylinder engines or anyone keeping an on-hand full set. If you maintain factory-spec performance and prefer the durability of iridium electrodes, this six-pack is a direct-fit option — provided you confirm part compatibility with your vehicle’s engine and trim before purchase.