A-Premium Iridium Platinum Spark Plugs — Pack of 6 Fine-Wire for V6 Engines, Long-Life

These A-Premium spark plugs combine an iridium-tipped center electrode with a platinum core to deliver improved ignition stability and extended service life compared with standard copper plugs. Designed with a fine-wire electrode and a 0.055–0.059 inch gap, this six-pack fits many V6 Ford-family applications and selected Land Rover and Mazda engines. The plugs use a 14 mm thread diameter, 17.98 mm reach and a 53 mm insulator height to match factory-style dimensions for proper fit and heat range.

Which engines and models will these spark plugs fit?

These plugs are intended for a broad range of V6 engines primarily from Ford and related brands; check your vehicle’s OEM reference number and engine specs before purchasing. They commonly fit 3.8L and 4.0–4.2L V6 applications in trucks, SUVs and some passenger cars across model years listed by the manufacturer.

• Compatible with Ford F-150 (selected years), E-150/E-250 Econoline series, Explorer, Ranger, Mustang, Taurus and more.
• Also matches fitments for Mazda B4000 V6, Land Rover LR3 V6 4.0L and several Lincoln and Mercury V6 models.
• Reference equivalents include 7316, TR551IX, XP6057, 7159 and TR551GP for cross-checking.

How do iridium and platinum materials benefit ignition and longevity?

Iridium on the center tip provides a very hard, wear-resistant surface that maintains a sharp firing point, improving spark consistency over time. The platinum core supports heat control and electrode stability, together extending the interval between replacements compared with conventional plugs.

• Fine-wire iridium tip for reliable spark and reduced voltage needs.
• Platinum center core for thermal stability and gradual wear profile.
• Recommended replacement interval of 80,000–100,000 miles under normal driving conditions.

What are the key specifications to confirm fit and performance?

Before ordering, verify thread diameter, reach and hex size match your engine’s original equipment. These plugs use a 14 mm thread diameter, 17.98 mm reach and a 5/8 inch (16 mm) hex for installation with standard tools, and the specified resistor value helps suppress radio frequency interference.

• Thread diameter: 14 mm; reach: 17.98 mm; insulator height: 53 mm.
• Hex size: 5/8 inch for socket installation; gap: 0.055–0.059 in (pre-gapped).
• Resistance: 5000 ohms to reduce ignition noise for electronics.

How should I install and maintain these spark plugs?

Install using the correct torque and a clean spark plug socket to avoid cross-threading or damage to the insulator. Check and re-gap only if necessary, and follow your vehicle’s service manual for torque specs and replacement intervals to maintain engine performance.

• Use a torque wrench and the vehicle manufacturer’s torque spec to install.
• Inspect boots, wires and ignition coils when replacing plugs to ensure full system health.
• Replace at 80,000–100,000 miles or per your vehicle manufacturer’s recommendation.

Who is this for: A-Premium’s Iridium Platinum fine-wire spark plugs are best for owners of V6 vehicles seeking a durable, OEM-style replacement that balances longevity and consistent spark performance. They suit DIY mechanics and professional installers who need factory-like fitment for older Ford V6 engines and compatible Land Rover, Mazda, Lincoln and Mercury models. Always confirm part cross-references and engine compatibility before purchase to ensure a correct match.