Best Spark Plugs For Infiniti G35

I remember the first time I pulled the old plugs out of my G35’s VQ35DE engine; they were absolutely toast. If you’re serious about keeping that iconic V6 running crisp, responsive, and fuel-efficient, choosing the best spark plugs for your Infiniti G35 is non-negotiable. Whether you need an affordable replacement or a maximum performance upgrade, this guide covers seven tested options, focusing on longevity, reliability, and ensuring you get that crisp throttle response every time you hit the gas. Let’s dive into what makes the biggest difference under the hood.

IMAGE	PRODUCT NAME	AMAZON LINK
	6 pc NGK V-Power Spark Plugs compatible with Infiniti G35…	View on Amazon
	NGK 4469 Iridium IX Spark Plugs LFR5AIX11 (6 Pack)	View on Amazon
	1406 Double Iridium Spark Plug for Infiniti EX35 FX35 G25…	View on Amazon
	6 pc NGK Iridium IX Spark Plugs compatible with Infiniti…	View on Amazon
	A-Premium 6PCS 4469 Iridium Platinum Spark Plugs Compatible…	View on Amazon
	UF550 Ignition Coil & 1406 Double Iridium Spark Plug for…	View on Amazon
	6 pc NGK Iridium IX Spark Plugs compatible with Infiniti…	View on Amazon

6 pc NGK V-Power Spark Plugs compatible with Infiniti G35 3.5L V6 2003-2007

If you’re looking for reliable, factory-standard performance without breaking the bank, the NGK V-Power plugs are a fantastic choice. These are copper core plugs, meaning they deliver excellent conductivity and a strong spark, making them a great direct replacement for the 2003-2007 Infiniti G35 VQ35DE. While they require more frequent replacement than iridium plugs, their proven reliability and affordability make them a go-to for many maintenance-minded G35 owners.

Key features that stand out:
– Genuine NGK Parts: Ensures quality and proper fitment.
– V-Groove Center Electrode: Improves ignitability and reduces quenching, providing reliable starts.
– Direct Replacement: Specifically engineered for 2003-2007 G35 models.

Pros:
– Excellent performance for the price point
– Strong conductivity due to copper core
– Trusted OEM brand reliability

Cons:
– Shorter lifespan (typically 30,000 miles) compared to premium metals.

Best for: Budget-conscious owners who prefer frequent, low-cost maintenance over long-life plugs.

Expert Opinion: While V-Power plugs are basic copper/nickel, they are excellent performers in naturally aspirated engines like the G35. Just be mindful of the shorter service interval required for these plugs.

NGK 4469 Iridium IX Spark Plugs LFR5AIX11 (6 Pack)

Stepping up significantly in durability and performance, the NGK Iridium IX plugs are what many G35 performance enthusiasts recommend. These plugs use a fine-wire Iridium center electrode, which concentrates the spark energy, leading to better cold-starting, faster acceleration, and more efficient combustion. They are a true performance upgrade that also offers excellent longevity, providing a great balance of cost and durability.

Key features that stand out:
– Iridium Fine-Wire Tip: Extremely durable material that allows for a consistently strong, stable spark.
– Exceptional Engine Life: Rated for around 40,000–50,000 miles.
– Improved Torque: Designed to maximize engine performance, especially in fuel-injected systems.

Pros:
– Superior durability and lifespan compared to copper
– Better idle stability and throttle response
– Less voltage required to bridge the gap

Cons:
– Higher initial cost than V-Power options.

Best for: Drivers seeking a performance boost and extended service life without going full double iridium.

Expert Opinion: The Iridium IX is a benchmark upgrade. The fine electrode reduces flame kernel quenching, which translates directly into crisper response from the VQ35DE.

1406 Double Iridium Spark Plug for Infiniti EX35 FX35 G25 G35 JX35 M35 M35h M56 Q50 Q70 QX60/Nissan Altima Maxima Murano Quest 350Z V6 Replaces # DILKAR7B11 (Set of 6)

If maximum longevity is your priority, these Double Iridium plugs are engineered to go the distance. Featuring iridium on both the center electrode and the ground electrode, these plugs maintain a stable spark and require minimal maintenance, boasting a working life of up to 100,000 kilometers (about 60,000+ miles). They provide superior cold-start capabilities and contribute to better fuel economy and lower emissions over their extended life cycle.

Key features that stand out:
– Double Iridium Construction: Provides the highest level of durability and spark consistency.
– Extended Service Life: Designed for maximum mileage intervals.
– Better Fuel Economy: Consistent and stable spark optimizes combustion efficiency.

Pros:
– Incredible lifespan, reducing replacement frequency
– Strong resistance to wear and oxidation
– Provides superior cold-start performance

Cons:
– Compatibility needs careful verification with specific G35 sub-models.

Best for: Drivers who want “install and forget” reliability for the longest possible service interval.

Expert Opinion: Double Iridium plugs are the pinnacle of longevity. For the G35, which has some rear plugs that are tedious to access, investing in 100k plugs saves significant labor over time.

6 pc NGK Iridium IX Spark Plugs compatible with Infiniti G35 3.5L V6 2003-2007

This package is another iteration of the excellent NGK Iridium IX plugs, specifically bundled and guaranteed for the earlier 2003-2007 G35 models. Just like the general 4469 model, these plugs offer a high-performance spark using the thin iridium tip, ensuring fast ignition and reduced misfires under load. This is a reliable, genuine NGK kit for those requiring confirmed fitment for their specific year range.

Key features that stand out:
– Guaranteed Fitment: Direct replacement parts specifically confirmed for 2003-2007 G35 3.5L V6.
– Genuine NGK Quality: Ensures materials and construction meet high standards.
– Improved Ignitability: Iridium center electrode allows for a more focused spark.

Pros:
– Excellent lifespan (40,000+ miles)
– Reliable performance upgrade over copper plugs
– Confirmed fitment takes out the guesswork

Cons:
– Primarily focuses on the VQ35DE (not VQ35HR) 2003-2007 years.

Best for: Owners of early model G35s (Coupe or Sedan) looking for the proven reliability of NGK Iridium IX plugs.

Expert Opinion: For the high-mileage VQ35DE engine, Iridium plugs are a worthwhile investment. They resist fouling better than copper and maintain their gap setting over long periods.

A-Premium 6PCS 4469 Iridium Platinum Spark Plugs Compatible with Nissan Xterra, Altima, Maxima, Pathfinder & Infiniti G35 & Hyundai Santa Fe & Kia Barrego & Toyota 4Runner, 2.7L-4.0L, 2001-2021

This A-Premium set offers a robust alternative, combining Iridium on the center electrode and Platinum on the ground electrode. This combination provides a high level of wear resistance and conductivity, engineered for optimal engine performance and longevity, often reaching the 80,000 to 100,000-mile replacement range. This set is versatile, covering a wide range of V6 Nissan/Infiniti engines, including the G35.

Key features that stand out:
– Iridium/Platinum Combination: Offers high durability and stability for a long life.
– Long Longevity: Recommended replacement interval of 80,000 to 100,000 miles.
– Wide Vehicle Fitment: Covers various G35 years and related Nissan/Infiniti models (4469 equivalent).

Pros:
– Excellent value for a platinum/iridium combination
– Extremely long replacement interval
– Consistent spark and efficient combustion

Cons:
– Not a specialized NGK product, though it shares core specifications.

Best for: Drivers prioritizing maximum mileage intervals and cross-compatibility with other VQ engines in their fleet.

Expert Opinion: The Iridium/Platinum combination is a highly durable design. While these plugs might require a quick check of the spark plug gap before installation, they offer excellent service life comparable to OEM high-mileage options.

UF550 Ignition Coil & 1406 Double Iridium Spark Plug for Nissan Altima Maxima Murano Pathfinder Quest 350Z/Infiniti EX35 FX35 G25 G35 JX35 M35 M35h Q50 Q70 QX60 3.5L V6 C1670 22448-JA10C 5C1727

This comprehensive kit provides both the spark plugs and the ignition coils. For G35s with higher mileage (usually over 100k miles), coils can start to weaken, leading to inconsistent performance and misfires. By replacing both the 6 coils and 6 Double Iridium spark plugs at the same time, you guarantee a completely refreshed ignition system. The plugs themselves are the long-life Double Iridium variant (100,000 km life).

Key features that stand out:
– Complete Ignition Overhaul: Includes 6 high-quality coils and 6 Double Iridium plugs.
– Double Iridium Plugs: Ensures maximum plug longevity (up to 100,000 km).
– Quality Coil Construction: Utilizes premium materials to resist heat cycling and ensure optimal voltage transfer.

Pros:
– Solves potential issues with both plugs and coils simultaneously
– Excellent value for a full ignition system tune-up
– Guaranteed smoother engine running and superior cold starts

Cons:
– Initial cost is significantly higher than just purchasing plugs alone.

Best for: High-mileage G35 owners performing a major ignition system maintenance update to eliminate misfires.

Expert Opinion: Replacing coils and plugs together is smart preventative maintenance on older VQs. A fresh, strong coil working with a brand-new double iridium plug will deliver the most powerful, consistent spark possible.

6 pc NGK Iridium IX Spark Plugs compatible with Infiniti G35 3.5L V6 2007-2008

Finally, we have the specialized NGK Iridium IX set for the later model G35s, specifically the 2007-2008 3.5L V6, which includes vehicles equipped with the VQ35HR engine (the higher-revving, dual-intake setup). These plugs are factory-specified to handle the slightly different demands of the HR engine, ensuring perfect fitment and maintaining the intended performance characteristics of these later model years.

Key features that stand out:
– Targeted Fitment: Confirmed compatibility for the 2007-2008 G35 models (including VQ35HR variants).
– Iridium Construction: Provides reliable, high-energy spark delivery.
– Direct Replacement: No modifications needed for installation.

Pros:
– Ideal choice for the potentially more sensitive VQ35HR engine
– Long lifespan reduces maintenance frequency
– Trusted OEM-quality replacement

Cons:
– Not compatible with earlier VQ35DE models.

Best for: Owners of the 2007-2008 Infiniti G35, especially those with the VQ35HR engine.

Expert Opinion: Fitment is crucial, especially when dealing with the transition years of the G35 engine lineup. Choosing a plug explicitly certified for the later 2007-2008 models ensures maximum engine efficiency and avoids potential heat range issues.

Comparison Short Insights

When choosing the best spark plugs for your Infiniti G35, the main decision boils down to your maintenance philosophy and budget.

For pure affordability, the NGK V-Power copper plugs can’t be beat, but remember you’ll be changing them every 30,000 miles. They offer excellent performance per dollar.

If you want a significant upgrade in durability, the NGK Iridium IX (4469) sets the standard, offering roughly double the lifespan of the copper options. They are the most popular performance upgrade for G35 owners.

For the longest possible service interval—meaning you only change them once every 80,000+ miles—you should opt for the Double Iridium or Iridium Platinum options (like the A-Premium or 1406 sets). These reduce maintenance headaches, especially for the hard-to-reach rear plugs.

Finally, if your G35 is showing signs of poor idle or hesitation along with high mileage, the UF550 Ignition Coil & Double Iridium Spark Plug Kit provides a comprehensive solution for total ignition system revitalization.

Final Verdict

Making the right choice for your G35 depends on your budget and how often you want to tackle the spark plug job.

Our Recommendation for Best Overall Value:
The NGK 4469 Iridium IX Spark Plugs win this category. They offer a fantastic blend of improved performance, reliable OEM quality, and an extended lifespan that justifies the higher initial cost over copper.

Our Recommendation for Longest Life/Least Hassle:
If you want to install them and forget them for years, the 1406 Double Iridium Spark Plug Set is the top choice. These plugs are engineered for the absolute longest service intervals.

Our Recommendation for High-Mileage Tune-Up:
If your G35 has over 100,000 miles and needs a full reset, the UF550 Ignition Coil & 1406 Double Iridium Spark Plug Kit offers the most comprehensive solution, guaranteeing peak ignition performance for years to come.

Comprehensive FAQs About Choosing the Best Spark Plugs for Your Infiniti G35

Q1: What is the difference between Copper, Iridium, and Double Iridium spark plugs for the G35?

A: The difference is primarily longevity and wear resistance. Copper (like NGK V-Power) is the best conductor but wears fastest, needing replacement around 30k miles. Iridium (Iridium IX) is much harder, resists wear, and lasts 40k–60k miles. Double Iridium or Iridium/Platinum plugs use the material on both electrodes, offering maximum wear resistance and an extended service interval of 80k–100k+ miles.

Q2: Should I pre-gap the spark plugs for my Infiniti G35 VQ35DE engine?

A: Most premium iridium and platinum spark plugs come pre-gapped for your engine from the factory. While they usually don’t need adjustment, it’s always wise to check the spark plug gap against your owner’s manual specification (typically 0.044 inches for the VQ35DE). If you are using copper plugs, you almost always need to check and adjust the gap. Be very careful adjusting iridium tips as the fine wire can be damaged easily.

Q3: How often should I replace the spark plugs on my G35?

A: This depends entirely on the material you choose. Copper/Nickel plugs should be replaced around every 30,000 miles. Standard Iridium plugs typically last between 40,000 and 60,000 miles. Double Iridium plugs are built for maximum longevity and can last 80,000 to 100,000 miles. Always refer to your spark plug manufacturer’s guidelines.

Q4: Will changing to Iridium plugs boost horsepower in my Infiniti G35?

A: While switching from worn-out plugs to any new plug will restore lost performance, changing to iridium won’t dramatically increase peak horsepower on a stock engine. Their main performance benefit is delivering a more stable, efficient spark, which translates to improved throttle response, better low-end torque, and better fuel economy than older, worn-out standard plugs.

Q5: Are the spark plugs the same for the VQ35DE (pre-2007) and VQ35HR (2007-2008) G35 engines?

A: No, not necessarily. While both are 3.5L V6 engines, the VQ35HR often requires a different heat range or specific plug design due to its higher compression and dual-throttle body setup. Always ensure you purchase a set explicitly compatible with your specific model year and engine code to prevent potential engine issues or misfires.

Q6: Can poor spark plugs cause my G35 to have bad gas mileage?

A: Yes, absolutely. A worn or fouled spark plug will cause incomplete combustion (misfiring), meaning fuel is wasted without generating power. Replacing old plugs with the best spark plugs for your Infiniti G35 ensures complete fuel burn, directly improving your gas mileage and reducing emissions.