Iridium Spark Plugs 8 Pack SP515 SP546 Compatible with Ford F150

In this review of the Iridium Spark Plugs 8 Pack, the focus is on drivers of mid-2000s Ford V8 vehicles who need a dependable replacement that restores smooth running. Installed as a set of eight, these plugs are presented as a direct-fit option for several 4.6L and 5.4L engines and aim to address common ignition problems such as misfiring and poor idling. The reviewer finds the main reason to buy is improved engine stability across the rev range, backed by the manufacturer's stated quality control and a 12-month warranty.

Key Features

• Reference Compatibility: Labeled with multiple reference numbers including SP515 and SP546 to match factory replacements for easy cross-referencing.
• Vehicle Fitment: Designed specifically for 2004-2008 Ford F-150 V8 5.4L and related Ford, Lincoln and Mercury V8 models so buyers can expect direct-fit installation.
• Iridium Tip: The iridium construction is intended to provide stable high voltage output and consistent ignition across the engine's speed range.
• Quality Control: Plugs undergo rigorous testing to reduce issues like backfiring, stalling, misfiring and poor fuel economy for more reliable daily driving.
• Package and Support: Sold as a set of eight with a 12-month worry-free warranty and dedicated customer support for replacements or concerns.

Who It's For

The Iridium Spark Plugs 8 Pack is best for owners of 2004-2008 Ford F-150 trucks with V8 5.4L engines and owners of compatible Ford Expedition, Mustang, Explorer, Lincoln Navigator/Mark LT and Mercury Mountaineer models who want a straightforward replacement that aims to restore smooth running and address ignition-related drivability issues.

Those with non-compatible engines, very high-performance builds, or who require a different electrode gap or specialized racing plugs should look elsewhere; this set is aimed at factory-equivalent replacement rather than custom tuning.

Pros & Cons

Pros

• Direct-fit compatibility across many 2004-2008 Ford and related V8 models simplifies installation and part matching.
• Iridium tips and stated quality testing contribute to improved ignition stability and reduced misfiring.
• Packaged as a set of eight with a 12-month warranty, offering value and post-purchase support.
• Customers report the truck runs smoothly after installation, confirming functional performance in real use.

Cons

• Limited to specific mid-2000s Ford and related models, so fitment must be checked carefully before purchase.
• Not intended as a performance racing plug; buyers seeking specialized gaps or extreme duty components will need a different option.

Specifications

Brand	A-NAFTULY
Reference Numbers	SP515, SP546, SP507, PZH14F, PZT2F
Package Included	Set of 8 iridium spark plugs
Vehicle Fitment	2004-2008 Ford F-150 5.4L and select Ford/Lincoln/Mercury V8 models
Warranty	12-month worry-free warranty
Purpose	Replacement ignition spark plugs for gasoline V8 engines

Our Verdict

The Iridium Spark Plugs 8 Pack is a pragmatic, cost-conscious replacement for owners of compatible mid-2000s Ford V8 vehicles who want restored engine smoothness and reliable ignition. With iridium tips, explicit reference numbers for cross-checking, and a one-year warranty, it represents good value for routine service and fixes common misfire and idling complaints without promising aftermarket performance gains.

Frequently Asked Questions

Are these plugs a direct fit for a 2006 F-150 5.4L?
Yes, the set is listed for 2004-2008 Ford F-150 V8 5.4L as a direct replacement for factory spark plugs.

How many plugs are included and is that enough for my V8?
This listing includes a set of eight iridium spark plugs, which is the correct quantity for the specified V8 engines listed.

Do these plugs fix misfiring and poor idling?
They are designed and quality tested to address common ignition issues such as misfiring, stalling and poor idling by restoring stable high voltage output.