NGK 7177 Spark Plug

NGK Iridium IX Spark Plug 7177

NGK Iridium IX Spark Plug 7177 is built for drivers maintaining older Chevrolet, Ford, GMC, and related applications that call for a tapered-seat spark plug with a 14 mm thread and .460-inch reach. It combines an iridium center electrode with a nickel ground electrode to support consistent ignition performance in a wide range of classic truck, van, and SUV fitments.

Key Features

• Iridium center electrode tip for stable spark delivery
• Copper core center electrode for efficient heat transfer
• Nickel ground electrode with taper-cut tip design
• 5,000 ohm resistance for ignition system compatibility
• Pre-gapped at .040 inch; verify against vehicle specifications before installation
• Tapered seat, 14 mm thread diameter, .460-inch reach, 5/8-inch hex
• NGK part number 7177, also listed as UR5IX

Product Details

The NGK Iridium IX Spark Plug line is focused on precise ignition performance and durability in demanding street applications. For vehicles such as Chevrolet C1500, GMC K1500, and Ford F-150, this plug provides an iridium firing tip paired with a copper-core center electrode to help maintain reliable combustion characteristics over time. NGK’s long OE manufacturing background and broad North American coverage make this a practical replacement choice for maintenance on older domestic trucks, vans, and SUVs.

This part cross-references Autolite XP24 and DENSO 5330 for the same application. The NGK 7177 is also referenced as UR5IX in catalog data.

What It Helps Address

• Hard starting caused by worn spark plug electrodes
• Rough idle from inconsistent ignition output
• Misfire conditions related to aged plugs
• Reduced throttle response from degraded spark quality
• Maintenance replacement on high-mileage Chevrolet, Ford, and GMC engines

Installation Notes and Tips

Confirm the vehicle-specific gap before installation. Catalog notes show applications calling for 0.035 inch, 0.044 inch, or 0.045 inch depending on engine and model year, so the plug should be checked and adjusted as needed before use. Verify thread reach, seat type, and hex clearance on the cylinder head before tightening. This plug is listed across many older Chevrolet P30, GMC P3500, and Ford Bronco applications, so matching the exact year and engine specification is important.

Quality Assurance

NGK is a major OE spark plug supplier with decades of automotive manufacturing experience and a reputation built around original-equipment standards. The 7177 Iridium IX Spark Plug is produced to support durability and consistent operational performance in a broad range of domestic vehicle applications.