NGK Spark Plug TR5IX 7397 Pack of 8 — Laser Iridium Ignition Plugs, Long-Life OEM Fit

NGK TR5IX 7397 Laser Iridium spark plugs are a set of eight OEM-grade ignition plugs engineered for long life and consistent performance.

These TR5IX 7397 plugs from NGK combine a fine iridium firing tip with proven electrode geometry to deliver reliable ignition and extended service intervals compared with conventional plugs. NGK supplies spark plugs to many vehicle manufacturers worldwide, so these parts are designed to meet strict factory tolerances. Before buying, check NGK's application guide for exact vehicle, engine and quantity fitment to ensure compatibility.

How do these spark plugs improve day-to-day engine performance?

Laser-welded iridium tips provide a stable, precise spark that supports smoother starts and more consistent combustion across operating conditions. That translates into fewer misfires, reliable throttle response and steadier idle in engines where these plugs are a correct fit.

• Fine iridium tip for concentrated spark energy
• Durable center electrode that resists erosion
• Stable combustion for consistent throttle and idle

What makes the TR5IX 7397 different from standard spark plugs?

Compared with conventional plugs, the TR5IX 7397 uses premium materials and precision manufacturing to extend service life and preserve ignition efficiency over time. That means fewer replacements and reduced performance drop-off between changes.

• Iridium center electrode lasts longer than nickel alloys
• Precise electrode geometry reduces ignition voltage requirement
• Manufactured to OEM-level dimensional tolerances

How should I confirm these plugs fit my vehicle?

NGK publishes a vehicle application guide that lists part numbers by make, model, year and engine. Cross-referencing the TR5IX 7397 on NGK's website or with your vehicle’s service manual ensures correct thread size, heat range and quantity before purchase.

• Check NGK’s online fitment tool for exact vehicle matches
• Confirm thread pitch, hex size and reach match factory specs
• Order eight if your engine calls for that quantity

What should I expect during installation and service intervals?

Installation is the same as for other spark plugs: sealant or anti-seize depends on vehicle requirements and torque should follow the OEM specification. Iridium plugs typically allow longer service intervals, but follow manufacturer recommendations for inspection and replacement.

• Tighten to OEM torque—do not overtighten
• Use recommended ignition boots and torque wrench when possible
• Inspect at intervals suggested by your vehicle maker

Who this is for: Automotive owners, mechanics and restoration professionals seeking a dependable replacement that matches factory-level specifications will appreciate the NGK TR5IX 7397 pack of eight. This set is suited for vehicles that specify NGK iridium plugs, drivers who prefer longer service life between tune-ups, and anyone wanting an OEM-quality ignition component for street, fleet or light-duty applications.