10 Best Spark Plugs For Toyota 4Runner Tested 2025

I’ve spent years tinkering under the hood of various 4Runners, and I know that choosing the right spark plug is critical for smooth operation. When you’re looking to maximize your engine’s fuel efficiency and maintain that reliable Toyota performance, settling for cheap plugs just won’t cut it. This guide focuses on identifying the best spark plugs for Toyota 4Runner models, covering generations from the 3rd to the 5th, ensuring you get everything from enhanced durability to quicker cold starts.

IMAGE	PRODUCT NAME	AMAZON LINK
	6 pc DENSO Standard Spark Plugs compatible with Toyota…	View on Amazon
	6 pc NGK Laser Iridium Spark Plugs compatible with Toyota…	View on Amazon
	6 pc DENSO Iridium Power Spark Plugs compatible with…	View on Amazon
	NGK 6619 Iridium Spark Plugs LFR6AIX-11-6 PCSNEW	View on Amazon
	ENA Set of 3 Ignition Coil with 6 Platinum Spark…	View on Amazon
	6 pc DENSO Platinum TT Spark Plugs compatible with Toyota…	View on Amazon
	6 pc NGK Iridium IX Spark Plugs compatible with Toyota…	View on Amazon
	6 pc DENSO Iridium TT Spark Plugs compatible with Toyota…	View on Amazon
	HYR Ignition Coils and Iridium Spark Plugs and Wires…	View on Amazon
	6 pc DENSO Iridium Long Life Spark Plugs compatible with…	View on Amazon

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

For those driving the beloved 3rd generation 4Runner (or equivalent models), these DENSO Standard Plugs offer OEM quality and reliability, which is exactly what these workhorse engines thrive on. DENSO has a strong reputation in the automotive world, earning awards for commitment to quality and engineering excellence. These standard plugs are engineered to virtually eliminate erratic starts and misfires, ensuring complete fuel ignition for efficient combustion.

Key features that stand out:
– Genuine DENSO Quality: Trusted OE supplier parts for reliable fitment.
– Improved Combustion: Unique ground electrode generates a larger spark nucleus.
– Reduce Misfires and Emissions: Engineered for cleaner, consistent firing, especially in older engines.

Pros:
– Excellent cost-effective OE replacement option.
– Proven reliability for older 3.4L V6 engines.
– Specifically designed to minimize fouling.

Cons:
– Durability lifespan is shorter compared to iridium or platinum plugs.

Best for: 3rd Generation 4Runner owners (1996-2002) prioritizing OEM fitment and reliability over extended lifespan.

Expert Opinion: While these are not exotic materials, DENSO standard plugs provide the most consistent performance for the 5VZ-FE engine (3.4L) and maintain the factory-recommended maintenance schedule perfectly.

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

NGK is a co-favorite with DENSO when it comes to factory-grade performance, and their Laser Iridium plugs are built for the modern 5th gen 4Runner (4.0L V6). These plugs utilize an iridium center electrode and a platinum ground electrode, offering the best combination of extreme longevity and sharp performance. If you want to install plugs and forget about them for 100,000 miles, this set is a superb choice.

Key features that stand out:
– Laser Iridium Construction: Iridium center with platinum ground for maximum durability.
– Genuine NGK Parts: Direct replacement quality specifically for the 4.0L V6 engine.
– Long Service Interval: Designed to match or exceed OE replacement schedules.

Pros:
– Exceptional lifespan, often exceeding 100,000 miles.
– Highly resistant to fouling and pre-ignition.
– Direct fitment for 2013-2020 models.

Cons:
– This premium technology comes with a higher initial price point.

Best for: 5th Generation 4Runner owners (2013-2020) looking for OE-equivalent plugs with the longest possible service life.

Expert Opinion: Laser Iridium is the technology Toyota often recommends for extended maintenance intervals, making these an excellent choice for drivers who use their 4Runner daily and require reliable, long-term performance.

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

If you use your 4Runner for high-performance driving, towing, or if you have made engine modifications, the DENSO Iridium Power plugs should be on your radar. Featuring an incredibly fine 0.4mm iridium tip, they deliver maximum spark energy. This finer tip results in a stronger, more focused spark, translating directly into superior fuel economy and noticeable power delivery, especially under load.

Key features that stand out:
– 0.4mm Iridium Tip: Thinner center electrode improves spark energy.
– U-Groove Ground Electrode: Tapered cut design reduces quenching and enhances flame travel.
– Maximum Performance: Designed to withstand extreme temperatures (over 4000 degrees).

Pros:
– Provides a measurable boost in throttle response and acceleration.
– Exceptional spark energy for more complete combustion.
– Genuine DENSO quality ensures proper fit.

Cons:
– Performance focus means the lifespan may be slightly shorter than the Iridium Long Life series.

Best for: 5th Generation 4Runner owners seeking improved throttle response and maximum engine efficiency.

Expert Opinion: The Iridium Power line prioritizes performance gains over maximum mileage, making them the choice for the enthusiast who wants the sharpest possible response from their 4.0L engine.

NGK 6619 Iridium Spark Plugs LFR6AIX-11-6 PCSNEW

NGK’s Iridium IX series is designed to handle a much wider heat range than traditional plugs, offering resilience against both carbon buildup (cold spots) and pre-ignition (hot spots). The patented triple-gasket sealing process is a massive plus, guaranteeing that combustion gases stay exactly where they belong, maximizing efficiency and preventing leaks.

Key features that stand out:
– Wider Heat Range: Versatile performance across various driving conditions.
– Triple Gasket Seal: Eliminates the risk of compression leakage.
– Resists Carbon Buildup: Fine-wire electrode design helps keep the tip clean.

Pros:
– Highly reliable sealing process.
– Excellent resistance to pre-ignition, ideal for hard use.
– Strong compatibility with fuel-injected systems.

Cons:
– Specific compatibility needs to be confirmed based on the vehicle year and engine type.

Best for: Drivers needing reliable, high-quality iridium performance suitable for varied climates and driving styles.

Expert Opinion: NGK Iridium IX plugs are often considered the sweet spot for many Toyota engines—offering great performance benefits without the top-tier cost of the Laser Iridium line.

ENA Set of 3 Ignition Coil with 6 Platinum Spark Plug and Wire Set Compatible with Toyota 4Runner T100 Tacoma Tundra 1995-2004 3.4L Replacement for UF156 C1041 90919-02212 5C1308 E679

This comprehensive kit is a lifesaver for owners of older 3.4L V6 models. If you’re experiencing misfires, rough idling, or a check engine light for circuit malfunctions, the issue might lie in the entire ignition system, not just the plugs. This set provides three ignition coils (which these engines require), six platinum spark plugs, and the necessary wire set, ensuring a complete ignition system overhaul.

Key features that stand out:
– Complete Ignition Solution: Includes coils, plugs (Platinum), and wires.
– OE Standard Reliability: Components are built to meet or exceed original equipment specifications.
– Fixes Common Failures: Specifically targets misfires, stalling, backfiring, and poor idling associated with aging systems.

Pros:
– Excellent value for a complete ignition system replacement.
– Platinum plugs offer better durability than standard plugs.
– Guaranteed compatibility for 3.4L engines from 1995-2004.

Cons:
– The quality of aftermarket coils can sometimes be hit-or-miss compared to OEM brands.

Best for: 3rd Generation 4Runner owners (3.4L) needing a full, budget-friendly ignition system refresh.

Expert Opinion: If your 3.4L 4Runner has over 150,000 miles and hasn’t had the coils or wires replaced, a kit like this is a pragmatic way to solve multiple potential issues at once, though careful attention should be paid to the coil reliability.

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 unique design for the 4th generation 4Runner (2003-2013). They use a platinum center electrode coupled with a titanium-enhanced alloy ground electrode. This twin-tip design minimizes quenching (the cooling of the spark), resulting in a more consistent and powerful spark compared to single-platinum plugs, leading to faster starts and improved efficiency.

Key features that stand out:
– Platinum TT Design: Twin-tip construction reduces quenching for a stronger spark.
– Titanium-Enhanced Alloy: Ground electrode offers improved resistance to wear.
– Faster Starts: Designed to provide quicker ignition response.

Pros:
– Better durability and performance than standard single-platinum plugs.
– Consistent spark delivery throughout the plug’s life.
– Ideal upgrade for the 4th Gen 4Runner.

Cons:
– Still slightly less durable than iridium plugs over the extreme long term.

Best for: 4th Generation 4Runner owners (2003-2013) looking for a reliable, step-up in performance from traditional platinum plugs.

Expert Opinion: Platinum TT plugs strike a fantastic balance between the longevity of precious metal and the performance of fine-wire technology, making them a great daily driver option.

6 pc NGK Iridium IX Spark Plugs compatible with Toyota 4Runner 4.0L V6 2003-2013

NGK’s Iridium IX line is tailored for enthusiasts and drivers who want sharp throttle response and sustained power. These plugs feature a fine-wire Iridium center electrode paired with nickel-alloy ground electrodes, optimizing them for maximum engine horsepower and torque. They are particularly effective in fuel-injected and turbocharged engines (though the stock 4Runner is not turbo, this resilience ensures excellent stability).

Key features that stand out:
– Fine-Wire Iridium Center: Maximizes spark focus for high performance.
– Precision Laser-Welded: Ensures electrode integrity under high heat.
– Optimized Performance: Designed to maximize horsepower and torque output.

Pros:
– Excellent responsiveness and smooth idle.
– High thermal stability and resistance to corrosion.
– Great fitment for the popular 4th Gen 4Runner.

Cons:
– Focus on performance means the lifespan might be slightly shorter than the OEM-style Laser Iridium.

Best for: 4th Generation 4Runner owners who want a noticeable performance boost and sharper engine response.

Expert Opinion: If you use your 4Runner for towing or off-roading where peak power delivery is needed, the NGK Iridium IX will ensure your ignition system keeps up with the demands. They are among the best spark plugs for toyota 4runner drivers prioritizing feel.

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

DENSO’s Iridium TT plugs take the twin-tip concept to the next level by utilizing iridium. This plug features an incredibly fine 0.4mm iridium center and a 0.7mm platinum ground electrode. This combination creates a powerful, focused spark that is highly resistant to wear, delivering improved durability, maximum performance, and better fuel economy than standard plugs. They are especially robust, capable of handling extreme compression and boost levels.

Key features that stand out:
– Iridium Twin Tip (TT): Super-fine electrodes provide superior power and efficiency.
– Maximum Spark Energy: Twin-tip design minimizes quenching losses.
– Improved Durability & Efficiency: Offers extended life while maintaining peak performance.

Pros:
– Considered a top-tier upgrade for performance and longevity.
– Handles high-stress conditions exceptionally well.
– Provides tangible improvements in fuel economy.

Cons:
– This is one of the more expensive options on the list.

Best for: 4th Generation 4Runner drivers seeking the highest balance of efficiency, durability, and performance.

Expert Opinion: The Iridium TT design is arguably DENSO’s finest innovation, offering performance comparable to racing plugs but with the longevity needed for a daily driven SUV.

HYR Ignition Coils and Iridium Spark Plugs and Wires Ignition Coils Pack Fit for Toyota, 1996-2002 4Runner, 1995-1998 T100, 1995-2004 Tacoma, 2000-2004 Tundra, 3.4L Replaces UF156 C1041

Similar to the ENA kit, this HYR package offers a comprehensive ignition overhaul for the older 3.4L V6 engine, but with an important distinction: it includes Iridium spark plugs. The kit provides three ignition coils made with high-quality copper wire, capable of generating 35,000+ volts for complete combustion. The inclusion of iridium plugs means significantly longer life and better performance than standard platinum or copper plugs found in similar kits.

Key features that stand out:
– Iridium Plugs Included: Provides long-lasting wear resistance and better fuel efficiency.
– High-Performance Coils: Capable of generating high voltage for complete combustion.
– Complete Kit: Includes 3 coils, 6 plugs, and wires for full replacement.

Pros:
– Best value for a full ignition replacement using iridium technology.
– Effective at solving cold start and rough idle problems.
– Better fuel economy due to complete combustion.

Cons:
– Buyers must verify the long-term reliability of the aftermarket coils.

Best for: Owners of 3rd generation 4Runners who need a full ignition system replacement but want the long-life benefits of iridium spark plugs.

Expert Opinion: Moving to iridium plugs in an older 3.4L engine is a great upgrade, as it drastically extends the maintenance interval compared to copper plugs, simplifying maintenance on these aging vehicles.

6 pc DENSO Iridium Long Life Spark Plugs compatible with Toyota 4Runner 4.0L V6 2003-2013

The DENSO Iridium Long Life series is built specifically for drivers who prioritize maintenance-free motoring. These plugs utilize a fine-wire 0.4mm iridium center electrode and a 0.7mm platinum ground electrode. This design combination ensures sustained, stable spark performance that can reliably last 100,000 miles or more, enduring the extreme temperatures associated with high-performance ignition systems found in the 4th generation 4Runner.

Key features that stand out:
– Sustained Spark Performance: Iridium center and platinum ground for extreme durability.
– 100,000+ Mile Lifespan: Engineered to match or exceed OE replacement intervals.
– 360 Degree Laser-Welded: Tapered cut improves firing performance and longevity.

Pros:
– Maximum possible lifespan among all plugs reviewed.
– Excellent fuel economy retention over time.
– OE quality fit and finish.

Cons:
– Performance gains are marginal compared to the Iridium Power or Iridium TT lines.

Best for: 4th Generation 4Runner owners who strictly follow the factory maintenance schedule and want a reliable, set-it-and-forget-it plug.

Expert Opinion: For most daily drivers, the Iridium Long Life plugs are the most sensible choice. They provide exceptional reliability and durability, ensuring peak engine condition for the longest period.

Comparison Insights: Choosing the Right Technology

When navigating the wide array of options for the best spark plugs for Toyota 4Runner, the choice often comes down to engine size (3.4L vs 4.0L) and your priorities (longevity vs. performance).

For the older 3.4L V6 engine (1996-2002), you must consider the entire ignition system. The ENA Platinum kit and the HYR Iridium kit offer the best value if your coil packs or wires are aging, with the HYR kit providing superior plug lifespan due to the iridium upgrade. If your coils are healthy, the DENSO Standard Plugs are the reliable, cost-effective OEM choice.

For 4.0L V6 engines (2003-2020), you are primarily choosing between DENSO and NGK, and between longevity and sharp performance:

• Maximum Longevity: The NGK Laser Iridium (for newer models) and the DENSO Iridium Long Life (for 4th Gen models) are your set-it-and-forget-it options, designed specifically for 100k+ mile service intervals.
• Performance and Response: Both the DENSO Iridium Power and the NGK Iridium IX are ideal. The DENSO Iridium TT offers a technological edge, combining the performance benefits of a fine wire tip with superior durability thanks to its twin-tip design.
• Platinum vs. Iridium: While DENSO Platinum TT is a great, robust option, iridium generally provides superior fouling resistance and a longer life, justifying the slightly higher cost for most 4Runner owners.

If you prioritize extreme longevity and OE compliance, stick with the Laser Iridium or Iridium Long Life lines.

Final Verdict

Deciding on the best spark plugs for Toyota 4Runner requires matching the plug to your specific engine (3.4L or 4.0L) and driving goals.

The Best Overall (4.0L): For modern 4Runners (4th and 5th Gen), the 6 pc DENSO Iridium TT Spark Plugs offer the ideal blend. They provide excellent performance gains with the highest level of durability available from a non-OE specific plug, making them a wise investment for better mileage and power.

Best for Factory Longevity (5th Gen 4.0L): You can’t beat the OE-level durability of the 6 pc NGK Laser Iridium Spark Plugs. If you want 100,000 miles of guaranteed trouble-free performance, this is the safest bet.

Best for Older 3.4L Owners: The HYR Ignition Coils and Iridium Spark Plugs and Wires Ignition Coils Pack provides the most complete and valuable solution. Upgrading the plugs to iridium while simultaneously replacing aging coils and wires solves the most common ignition issues for older 4Runners efficiently.

Best Spark Plugs For Toyota 4Runner FAQ

Q: What is the recommended spark plug replacement interval for a Toyota 4Runner?

A: The required interval varies significantly based on the plug type and engine generation. Toyota generally recommends replacing standard copper or single platinum plugs every 30,000 miles. However, modern iridium and laser iridium spark plugs, like the NGK Laser Iridium, are designed to last 100,000 to 120,000 miles. Always check your owner’s manual or rely on the high-mileage claims of genuine iridium plugs.

Q: Should I choose Iridium or Platinum spark plugs for my 4Runner?

A: For modern 4Runner models, Iridium is generally the superior choice. Iridium is harder and has a higher melting point than platinum, allowing for a much finer electrode tip. This results in a stronger, more consistent spark, better resistance to fouling, and a much longer lifespan (often 3-4 times longer than standard platinum plugs). Platinum plugs, like the DENSO Platinum TT, are a good mid-range option, but iridium offers the best long-term value.

Q: What are the common symptoms that indicate my 4Runner needs new spark plugs?

A: If your 4Runner needs new spark plugs, you might notice rough idling (the engine vibrates unevenly at a stop), engine misfires (a sudden stutter or loss of power), difficulty starting, poor acceleration, or a noticeable drop in gas mileage. In severe cases, a Check Engine Light may illuminate, indicating a cylinder misfire code.

Q: Do I need to gap the new spark plugs before installing them in my Toyota 4Runner?

A: Most modern platinum and iridium spark plugs come pre-gapped from the factory and are intended to be installed as-is. However, it’s always wise to confirm the gap setting against the manufacturer’s specification for your specific 4Runner engine (e.g., 3.4L V6 or 4.0L V6) using a wire-style gap gauge. Never attempt to adjust the gap on fine-wire iridium plugs, as you risk damaging the delicate tip.

Q: Why do some spark plug kits for the older 3.4L V6 include ignition coils?

A: The Toyota 3.4L V6 (found in the 3rd Gen 4Runner) uses a coil-on-plug system, but only on half of the cylinders (3 coils for 6 plugs), with spark plug wires running to the other three. Since these older vehicles often experience degradation in both the coils and the wires after 15-20 years, many retailers package them with the spark plugs (often the best spark plugs for Toyota 4Runner owners of this generation) to ensure a complete and reliable ignition system overhaul.

Q: Is there a difference between the spark plugs required for the 3.4L V6 and the 4.0L V6 4Runner engines?

A: Yes, absolutely. The 3.4L (5VZ-FE) engine found in 3rd Gen models requires different plugs with specific heat ranges and threading, often favoring standard or platinum construction. The 4.0L V6 (1GR-FE) found in 4th and 5th Gen models is designed for much higher-heat, high-efficiency plugs, and almost exclusively uses iridium or laser iridium technology for optimal performance and longevity. Always double-check compatibility by year and engine size.