BDFHYK Iridium Spark Plugs for Ford F-150 5.4L V8 2004–2008 — 8-Pack, OE-Fit Long-Life

BDFHYK SP546 iridium spark plugs: an 8-pack replacement engineered to restore reliable ignition and long-lasting performance for 2004–2008 Ford F-150 5.4L V8 engines.

These BDFHYK SP546 plugs use a fine iridium center electrode and high-density ceramic insulators to deliver consistent sparks, improved combustion efficiency, and OE-level durability. They are offered as a direct-fit aftermarket option compatible with many Ford and Lincoln vehicles using the same footprint and heat range. The set of eight covers a full V8 tune-up and includes plugs that meet common replacement part numbers used by technicians and DIY mechanics.

How do these plugs affect engine performance?

Replacing worn spark plugs with BDFHYK SP546 iridium plugs helps restore crisp ignition timing and more complete fuel combustion. Drivers often notice smoother idle, steadier throttle response, and reduced misfires when plugs are installed correctly.

• Finer iridium tip promotes a more concentrated spark for reliable ignition.
• High-density ceramic insulator resists fouling and voltage leakage.
• OE-style design maintains factory heat range and gap specifications.

Are these plugs compatible with my Ford F-150 or other vehicles?

The SP546 set is listed for Ford F-150 5.4L V8 model years 2004–2008 and also fits many Expedition and Ford Super Duty applications that share the same replacement number. Always confirm fitment by checking your vehicle’s year, make, model and the OE or service manual part number before purchase.

• Direct fit for 2004–2008 Ford F-150 5.4L V8 engines.
• Compatible with several Expedition, F-Series, and Lincoln Navigator/Mark LT models when matching OE numbers.
• Cross-references include part numbers like SP546, SP-546, SP515, and related OE codes.

What is the expected service life and reliability?

BDFHYK rates these iridium plugs for an economic service life typically between 30,000 and 40,000 kilometers under normal driving conditions. They are manufactured to TS16949-aligned practices and use durable materials to help extend reliable operation compared with standard copper plugs.

• Iridium center electrode for long wear resistance.
• Robust ceramic insulator for electrical isolation and mechanical strength.
• Designed to meet OE performance and durability expectations.

How should I install and maintain them for best results?

Install using the correct torque values and a clean, dry spark plug well to avoid cross-threading or contamination. Re-check ignition timing and perform a test drive after installation to confirm smooth operation; replace in matched sets for balanced performance across cylinders.

• Use a torque wrench and follow the vehicle manufacturer’s torque spec.
• Replace all eight plugs at the same time for the V8 engine.
• Inspect ignition wires/coils and seals while replacing plugs.

Who is this for: BDFHYK SP546 iridium spark plugs are intended for Ford F-150 owners and mechanics seeking a cost-effective, OE-style iridium replacement for 2004–2008 5.4L V8 engines. They suit drivers who want to restore ignition consistency and combustion efficiency without stepping up to specialty motorsport plugs. Prioritize correct fitment checks and standard installation practices to achieve the best longevity and performance from this eight-piece set.