Best Spark Plugs For 5th Gen 4Runner

When I bought my 5th Gen 4Runner, one of the first things I learned was the importance of proper maintenance, especially when considering off-roading or high-mileage driving. Switching out the stock spark plugs after their service interval can feel like giving your engine a refreshing breath of air—you immediately notice the restored pep, smoother idle, and sometimes even a little bump in fuel efficiency. Choosing the best spark plugs for 5th Gen 4Runner (which typically use the robust 4.0L V6 engine) means balancing longevity, reliability, and ignition performance. I’ve put together a detailed look at the top contenders to help you decide which set is right for your Toyota.

IMAGE	PRODUCT NAME	AMAZON LINK
	6 pc NGK Laser Iridium Spark Plugs compatible with Toyota…	View on Amazon
	NGK 4469 Iridium IX Spark Plugs LFR5AIX11 (6 Pack)	View on Amazon
	6 pc DENSO Iridium Power Spark Plugs compatible with…	View on Amazon
	6 pc DENSO Standard Spark Plugs compatible with Toyota…	View on Amazon
	NGK 6619 Iridium Spark Plugs LFR6AIX-11-6 PCSNEW	View on Amazon
	6 pc DENSO Platinum TT Spark Plugs compatible with Toyota…	View on Amazon
	A-Premium Set of 6 Ignition Coil Pack and Iridium Spark…	View on Amazon

6 pc NGK Laser Iridium Spark Plugs compatible with Toyota 4Runner 4.0L V6 2013-2020

If you’re looking for the gold standard factory replacement for your newer 5th Gen 4Runner, the NGK Laser Iridium series is essentially the definition of OEM quality. These plugs are engineered to deliver the precise spark needed for the 4.0L V6, ensuring reliable startup and maintaining the factory-expected engine performance throughout their extensive lifespan. They are built specifically to match the strict requirements of late-model Toyota engines.

Key features that stand out:
* Genuine NGK Parts: Ensures high reliability and consistent quality.
* Direct replacement auto parts: Designed specifically for Toyota 4.0L V6 2013-2020.
* Laser Iridium: Provides exceptional longevity, often matching the 100,000-mile factory interval.
* Includes original packaging and hardware: Simplifies installation and guarantees authenticity.

Pros:
* OEM quality ensures perfect compatibility and reliability.
* Exceptional lifespan reduces maintenance frequency.
* Provides consistent, powerful spark necessary for modern engines.

Cons:
– These are often the higher priced option due to their OEM status.

Best for:
Drivers seeking the absolute best factory replacement quality and longevity for a 2013-2020 4Runner.

Expert Opinion: NGK Laser Iridium plugs are considered the benchmark for modern Toyota engines. While the initial cost might be slightly higher, the peace of mind and long-term performance retention make them a worthwhile investment for serious 4Runner owners.

NGK 4469 Iridium IX Spark Plugs LFR5AIX11 (6 Pack)

The NGK Iridium IX plugs are often chosen by enthusiasts looking for a noticeable performance upgrade over standard OEM plugs, even if they sacrifice a small amount of the Laser Iridium’s extreme longevity. These feature a fine-wire Iridium center electrode, which translates to a sharper, more focused spark. This design choice helps maximize combustion efficiency and can lead to a slight increase in throttle response and torque, making them popular for engines that might see light modifications or rigorous use.

Key features that stand out:
* Fine-wire Iridium center electrode: Promotes maximum engine efficiency and torque.
* Extreme performance upgrade: Delivers a superior spark compared to typical nickel plugs.
* Lifetime at 40,000–50,000 miles: A shorter lifespan than Laser plugs, but excellent performance during that time.
* Designed for fuel-injected and turbo engines: Optimized combustion characteristics.

Pros:
* Improved ignition performance and sharper throttle response.
* Excellent resistance to fouling and high heat.
* Often more affordable than the Laser Iridium line.

Cons:
– Requires replacement significantly sooner than the 100,000-mile Laser series.

Best for:
The 5th Gen owner prioritizing a slight performance edge and sharper engine responsiveness.

Expert Opinion: The Iridium IX is a fantastic mid-grade choice. While the longevity is reduced, many drivers feel the enhanced ignition and cleaner burn are worth the trade-off, especially if you enjoy routine maintenance.

6 pc DENSO Iridium Power Spark Plugs compatible with Toyota 4Runner 4.0L V6 2014-2017

DENSO is another powerhouse in the Toyota OE world, and their Iridium Power plugs are designed with pure performance in mind. Featuring an incredibly thin 0.4mm iridium tip, these plugs deliver a larger, more concentrated spark than many competitors. This superior spark energy is key to achieving maximum performance and potentially superior fuel economy by ensuring a complete burn of the air-fuel mixture, even under high stress or temperature.

Key features that stand out:
* 0.4mm iridium tip: Provides the smallest, most efficient center electrode tip available.
* Tapered cut, U-Groove ground electrode: Increases spark energy while reducing quenching.
* Maximum performance: Designed specifically for performance and power applications.
* Withstands temperatures greater than 4000 degrees: Highly durable under extreme conditions.

Pros:
* Industry-leading thin iridium tip maximizes spark focus and power.
* Proven ability to increase power and fuel efficiency.
* Excellent heat tolerance for hard-working engines.

Cons:
– The performance focus means they may not always reach the 100k lifespan of OEM options.

Best for:
The 4Runner owner who demands maximum combustion efficiency and responsive power from their V6.

Expert Opinion: DENSO’s unique manufacturing process results in an incredibly robust plug focused on delivering maximum spark energy. If you tow often or run higher octane fuels, the Iridium Power plugs handle the heat beautifully.

6 pc DENSO Standard Spark Plugs compatible with Toyota 4Runner 3.4L V6 1996-2002

While this particular set is designed for the older 3rd Generation 4Runner (3.4L V6), it highlights DENSO’s commitment to quality even in standard copper construction. These plugs are built to reliable OE specifications, focusing on consistent starts and robust combustion to meet emissions standards. They are an excellent, budget-friendly option for owners of older models seeking to eliminate misfires and restore smooth operation without investing in premium materials like iridium or platinum.

Key features that stand out:
* Reduce emissions and misfires: Designed for complete fuel ignition in the combustion chamber.
* Unique ground electrode: Generates a larger spark nucleus at the point of ignition.
* Genuine DENSO Parts: Ensures high quality and reliability.
* Superior flame travel: Produces more complete, consistent, and efficient combustion.

Pros:
* Highly effective at eliminating misfires in older engines.
* Very cost-effective for routine maintenance.
* Proven quality backed by DENSO’s manufacturing pedigree.

Cons:
– These copper plugs require much more frequent replacement than iridium or platinum types.

Best for:
Owners of 3rd Gen 4Runners (1996-2002) looking for reliable, high-quality standard replacement plugs. Not suitable for 5th Gen 4Runners.

Expert Opinion: For older engines not requiring complex precious metal electrodes, standard plugs offer the best value for maintaining basic reliability. Just remember to adhere strictly to the shorter service interval recommendations.

NGK 6619 Iridium Spark Plugs LFR6AIX-11-6 PCSNEW

The NGK 6619 is another excellent option in the Iridium IX family, offering similar high-performance features but often covering a slightly different range of heat specifications suitable for the 4.0L V6. A key advantage of these plugs is their ability to operate effectively across a wider thermal range. This means they resist carbon buildup during slow city driving but can still handle high-temperature demands during towing or sustained highway speeds without risking pre-ignition.

Key features that stand out:
* Wider heat range operation: Excellent for diverse driving conditions (city and highway).
* Resists carbon buildup and pre-ignition: Keeps the electrode clean and firing optimally.
* Patented triple gasket sealing process: Eliminates the risk of combustion gas leakage.
* Iridium Spark Plugs: Ensures durable, reliable performance.

Pros:
* Versatile performance across varying engine temperatures.
* Triple gasket ensures a complete seal and proper heat transfer.
* Excellent choice for daily drivers who also weekend off-road.

Cons:
– Similar to other IX plugs, the longevity is good but doesn’t hit the 100k mark.

Best for:
The 5th Gen driver who experiences a wide range of driving conditions and needs thermal stability.

Expert Opinion: NGK’s patented triple gasket is a subtle but critical feature, ensuring the plug is securely seated and heat transfer is maximized, which is crucial for V6 longevity.

6 pc DENSO Platinum TT Spark Plugs compatible with Toyota 4Runner 4.0L V6 2003-2013

The DENSO Platinum TT (Twin Tip) plugs offer a fantastic balance between the cost of standard plugs and the extreme longevity of iridium. These utilize both a platinum center electrode (1.1mm) and a titanium-enhanced alloy ground electrode. The twin-tip design reduces the amount of metal that gets in the way of the spark (quenching), resulting in a more potent, consistent spark compared to typical platinum plugs. This makes them a strong contender for owners of early 5th Gen (2010-2013) and 4th Gen 4Runners.

Key features that stand out:
* Platinum TT (Twin Tip) design: Enables consistent performance and a powerful spark.
* Faster starts: Improved design provides quick, reliable ignition.
* Improved durability: Titanium-enhanced ground electrode extends life.
* Reduced quenching: Creates a less obstructed, more robust flame kernel.

Pros:
* Superior durability and spark quality compared to standard single-platinum plugs.
* Excellent lifespan, bridging the gap between copper and iridium.
* Great value for early 5th Gen owners.

Cons:
– Platinum is generally not as hard or long-lasting as iridium in extreme heat.

Best for:
4Runner owners (especially 2010-2013 models) seeking long-lasting precious metal performance without the full cost of iridium.

Expert Opinion: The Platinum TT design is a cleverly engineered solution. It delivers reliability and endurance that easily surpasses copper and standard platinum plugs, making it a very strong mid-range option.

A-Premium Set of 6 Ignition Coil Pack and Iridium Spark Plugs Compatible with Toyota 4Runner 2003-2009, Tundra 2005-2011, 4.0L

This A-Premium kit is an excellent value proposition, though it targets the 4th Generation 4Runner (2003-2009) engine, which uses the same 4.0L V6 as the 5th Gen. The primary benefit here is that you’re replacing two crucial components—the ignition coils and the spark plugs—simultaneously. Ignition coils often degrade around the same time as spark plugs, leading to misfires. This kit ensures a complete restoration of the ignition system using robust iridium spark plugs and new coil packs.

Key features that stand out:
* Complete Ignition System Overhaul: Includes 6 coils and 6 Iridium spark plugs.
* Spark Plug Material: Iridium + Nickel: Ensures stability and extended life.
* Guaranteed Fitment: Compatible with 4.0L V6 models 2003-2009 (and some early 5th Gens may share components).
* Improved Performance: A-Premium claims improved fuel efficiency and faster starting up.

Pros:
* Unbeatable value by bundling new coils with new plugs.
* Solving misfire issues is much easier when replacing both components at once.
* Iridium construction ensures good lifespan for the plugs.

Cons:
– The quality of aftermarket coils may not always match genuine Toyota/OEM parts.

Best for:
4th Gen or early 5th Gen 4Runner owners facing persistent misfires who want a complete, budget-conscious ignition system replacement.

Expert Opinion: While we prioritize genuine DENSO or NGK plugs, a full ignition kit like this is often the most economical and effective fix for a higher-mileage 4Runner struggling with persistent misfires across multiple cylinders.

Comparison Short Insights

When evaluating the Best Spark Plugs For 5th Gen 4Runner (2010+), the biggest decision is balancing longevity versus performance. The 5th Gen 4Runner uses the 1GR-FE 4.0L V6, which performs best with plugs that meet high heat and durability requirements.

For maximum longevity and closest match to the factory part, the NGK Laser Iridium set is the undisputed champion, designed to reliably hit that 100,000-mile mark. If you’re willing to trade some life for enhanced ignition and a crisper feel behind the wheel, both the NGK Iridium IX (4469/6619) and the DENSO Iridium Power are phenomenal choices, offering thinner electrodes and superior spark focusing.

The DENSO Platinum TT offers a great middle ground, proving to be an excellent, durable upgrade for early 5th Gen models (2010–2013) where budget is a greater consideration than achieving the absolute maximum performance of the thin-tip iridium models.

Final Verdict

Choosing the right plug depends entirely on your priority:

If Your Priority is Maximum Longevity (Set it and Forget it):

Go with the 6 pc NGK Laser Iridium Spark Plugs compatible with Toyota 4Runner 4.0L V6 2013-2020. These are built to meet or exceed Toyota’s 100k service interval, offering peace of mind and factory reliability.

If Your Priority is Enhanced Performance and Response:

We recommend the 6 pc DENSO Iridium Power Spark Plugs compatible with Toyota 4Runner 4.0L V6 2014-2017. Their 0.4mm tip technology delivers the sharpest, most focused spark, translating directly into responsive acceleration and maximum efficiency.

If Your Priority is Value and Mid-Range Durability:

The 6 pc DENSO Platinum TT Spark Plugs compatible with Toyota 4Runner 4.0L V6 2003-2013 provides fantastic performance and a long lifespan without the premium cost associated with thin-wire iridium plugs, making it a stellar option for budget-conscious owners.

Best Spark Plugs For 5th Gen 4Runner: Comprehensive FAQ

Q1: What kind of spark plugs does the 5th Generation 4Runner (4.0L V6) require?

A: The 5th Gen 4Runner (2010-Present) requires high-quality, long-life plugs, typically Iridium. Toyota generally recommends Iridium plugs for this engine (the 1GR-FE) due to their durability, high heat resistance, and ability to maintain performance over long service intervals, usually up to 100,000 miles.

Q2: What is the recommended service interval for spark plug replacement on a 5th Gen 4Runner?

A: For the factory-installed or OEM-equivalent Iridium spark plugs (like NGK Laser Iridium), the recommended service interval is typically every 100,000 to 120,000 miles. If you use performance-focused Iridium IX plugs, the interval is shorter, often around 40,000 to 50,000 miles.

Q3: Is it better to choose NGK or DENSO for my Toyota 4Runner?

A: Both NGK and DENSO are high-quality manufacturers and are considered OE (Original Equipment) suppliers for Toyota. There is no major difference in reliability between the top-tier NGK Laser Iridium and premium DENSO Iridium Power lines; the best choice often comes down to personal preference or the specific performance characteristics you are seeking (e.g., DENSO for the thinnest tip, NGK for exact factory match).

Q4: Do I need to gap my new Iridium spark plugs?

A: Most modern Iridium spark plugs, especially those from NGK and DENSO, come pre-gapped and ready for installation in your 4Runner’s 4.0L V6 engine. Attempting to manually adjust the spark plug gap on fine-wire iridium tips can damage the delicate electrode. Always confirm the required gap in your owner’s manual (usually around 0.043 inches for the 4.0L V6) and only verify, never adjust, iridium plugs.

Q5: Will new spark plugs improve my 4Runner’s gas mileage?

A: If your existing spark plugs are worn out, fouled, or significantly overdue for replacement, installing new, efficient Iridium spark plugs will definitely restore and potentially improve your fuel efficiency. Worn plugs cause weak combustion, forcing the engine to work harder. New plugs ensure a complete burn, maximizing power delivery and efficiency.

Q6: If my 4Runner is misfiring, should I replace the coils too?

A: In high-mileage 4Runners (over 150,000 miles), ignition issues are often caused by both worn plugs and degrading ignition coils. If a plug replacement doesn’t completely resolve your misfires, or if you notice cracks or corrosion on the coil boots, replacing the ignition coil packs (like those found in the A-Premium kit) along with the plugs is highly recommended for a complete fix.