Best Spark Plugs For Toyota 4Runner: Compare Fit and Plug Types

#1 · Best Overall

1. NGK Laser Iridium Plugs

• Core Material: Iridium
• Top Material Type: Iridium
• Weight: 11.52 oz
• Gap Size: 0.04 in

Best for: 2013–2020 4.0L V6 owners.

Why it ranks #1: The six-plug set explicitly fits 4.0L V6 4Runners from 2013–2020 and uses iridium construction, giving this listing notably clear coverage.

NGK Laser Iridium plugs arrive as a six-piece set specified for 2013–2020 Toyota 4Runner 4.0L V6 models, giving owners a direct-replacement option for a complete plug change. Iridium construction and the listed 14mm thread size make this set especially relevant to buyers seeking NGK plugs for that stated application.

The stated 2013–2020 4.0L V6 compatibility helps narrow the application to a defined 4Runner range, while the six-piece pack supplies the plugs for a set replacement. NGK Laser Iridium construction gives buyers the specified electrode material rather than a copper or platinum alternative. The listing also identifies a 0.04-inch gap and includes original packaging and hardware, useful details when planning parts and installation. It is a direct-replacement listing, but its fit range is not universal across 4Runner generations.

Skip it if you own a 1996–2002 3.4L V6; the DENSO Standard set B0827ZFF67 lists that generation instead.

For owners of a 2013–2020 4.0L V6 4Runner seeking a six-plug NGK Laser Iridium replacement set, this listing provides a clearly stated application. Its boundary is the listed engine and year range; other 4Runner versions are not specified.

Listed on Amazon as: 6 pc NGK Laser Iridium Spark Plugs for Toyota 4Runner 4.0L V6 2013-20

#2 · Long-Life Iridium

2. DENSO Iridium Long Life Plugs

• Core Material: Iridium
• Top Material Type: Iridium
• Weight: 11.52 oz
• Gap Size: 0.04 in

Best for: 2003–2013 4.0L V6 replacement.

Why it ranks #2: This six-piece DENSO set lists 4.0L V6 fitment for 2003–2013 and specifies an iridium center electrode with a platinum ground strap.

A fine-wire 0.4mm iridium center electrode defines this DENSO Iridium Long Life set, which is listed for 2003–2013 Toyota 4Runner 4.0L V6 models. Six plugs give owners of those trucks a generation-specific option, while the listing also identifies a platinum ground strap.

The stated 2003–2013 4.0L V6 compatibility helps owners target the listed 4Runner generation, and the six-plug pack provides a complete quantity for a set replacement. DENSO’s 0.4mm fine-wire iridium center electrode is paired with a platinum ground strap, combining two specifically identified electrode materials. The product description associates a larger spark with power and fuel-economy benefits, while the long-life designation gives buyers a maintenance-oriented choice. Its application remains limited to the listed engine and years.

Skip it if you have a 2014–2017 4.0L V6; the DENSO Iridium Long Life set B0D1S7ZM7T lists those years.

Owners maintaining a 2003–2013 4.0L V6 4Runner can consider this six-piece DENSO long-life set for its fine-wire iridium center and platinum ground strap. Its stated year range is the key fit boundary.

Listed on Amazon as: 6 pc DENSO Iridium Long Life Spark Plugs for Toyota 4Runner 4.0L V6 2003-13

#3 · Later-Model Iridium

3. DENSO Iridium Long Life Plugs

• Weight: 11.5 oz

Best for: 2014–2017 long-life iridium.

Why it ranks #3: The listing covers 4.0L V6 4Runners from 2014–2017 and identifies a 0.4 mm iridium center electrode and 0.7 mm platinum ground electrode.

A 0.4mm iridium center electrode paired with a 0.7mm platinum ground electrode defines DENSO’s Iridium Long Life set for 2014–2017 4Runner 4.0L V6 models. The six-piece listing gives owners a specific replacement option with both electrode materials identified.

The stated 2014–2017 4.0L V6 fitment identifies the intended 4Runner application, while six plugs provide a set quantity for owners planning replacement. DENSO pairs a fine-wire 0.4mm iridium center electrode with a 0.7mm platinum ground electrode, and the listing identifies the product as Iridium Long Life. The description connects a larger spark with power and fuel-economy benefits, without giving measured outcomes. This long-life option is distinct from the DENSO Iridium Power set listed for the same years.

Skip it if you have a 2003–2013 4.0L V6; the DENSO Iridium Long Life set B0B7KSHX6Y lists those earlier years.

This six-piece DENSO set fits the stated needs of 2014–2017 4.0L V6 4Runner owners seeking iridium long-life construction with a platinum ground electrode. Its year range is the main boundary for other generations.

Listed on Amazon as: 6 pc DENSO Iridium Long Life Spark Plugs for Toyota 4Runner 4.0L V6 2014-17

#4 · Twin-Tip Design

4. DENSO Iridium TT Plugs

• Core Material: Iridium
• Top Material Type: Iridium
• Weight: 11.52 oz
• Gap Size: 0.04 millimeters

Best for: Iridium TT for 2003–2013.

Why it ranks #4: This six-plug set is listed for 2003–2013 4.0L V6 models and combines a 0.4 mm iridium tip with a 0.7 mm platinum ground electrode.

DENSO Iridium TT combines a 0.4mm iridium center electrode with a 0.7mm platinum ground electrode, giving this six-pack a specified twin-tip configuration. It is listed for 2003–2013 Toyota 4Runner 4.0L V6 models, making its application clear for that generation.

The stated 2003–2013 4.0L V6 compatibility helps identify the intended 4Runner application, while six plugs supply a full set quantity. DENSO’s Iridium TT pairs a 0.4mm iridium center electrode with a 0.7mm platinum ground electrode; the description presents this twin-tip combination as supporting endurance and power. The listed 0.04-millimeter gap is another specification to note when reviewing the part. Its application is for the earlier 4.0L V6 range, not every 4Runner.

Skip it if you own a 2014–2017 4.0L V6; the DENSO Iridium Long Life set B0D1S7ZM7T lists that later range.

Owners of a 2003–2013 4.0L V6 4Runner seeking DENSO twin-tip construction can weigh this six-piece Iridium TT set. Its stated application does not cover the later 2014–2017 4.0L V6 models.

Listed on Amazon as: 6 pc DENSO Iridium TT Spark Plugs for Toyota 4Runner 4.0L V6 2003-13

#5

5. NGK Iridium IX Plugs

• Weight: 11.5 oz

Best for: Fine-wire NGK Iridium IX.

Why it ranks #5: The listing identifies a six-plug set for 2003–2013 4.0L V6 4Runners, with a fine-wire iridium center electrode and nickel-alloy ground electrodes.

NGK’s fine-wire iridium center electrode and precision laser-welded construction define this Iridium IX six-pack. The listing also names nickel-alloy ground electrodes and suitability for fuel-injected and turbocharged engines, giving buyers specific construction and engine-use details to weigh.

The fine-wire iridium center electrode is paired with a nickel-alloy ground electrode, a combination the listing connects to maximum horsepower and torque. Precision laser-welded electrode construction is another explicit feature, useful to shoppers comparing how the plug is assembled. The product is described for fuel-injected and turbocharged engines, and the six-piece quantity is stated. However, unlike several other options here, the supplied details do not name Toyota 4Runner years, engine size, or a specific 4Runner fitment range.

Skip it if you need a stated 4Runner application; the NGK Laser Iridium set B0B7LTWTTJ lists 2013–2020 4.0L V6 fitment.

This NGK Iridium IX set suits shoppers focused on fine-wire iridium construction, laser-welded electrodes, and the listed fuel-injected or turbocharged use. Its boundary for a 4Runner buyer is the absence of a specified year and engine range.

Listed on Amazon as: 6 pc NGK Iridium IX Spark Plugs for Toyota 4Runner 4.0L V6 2003-13

#6

6. DENSO Iridium Power Plugs

• Core Material: Platinum
• Top Material Type: Iridium
• Weight: 11.52 oz
• Gap Size: 0.04 in

Best for: 2014–2017 Iridium Power.

Why it ranks #6: This six-piece option lists 4.0L V6 fitment for 2014–2017 and features a 0.4 mm iridium tip plus a tapered-cut U-Groove ground electrode.

DENSO’s tapered-cut U-Groove ground electrode and 0.4mm iridium tip make this Iridium Power set a feature-specific option for 2014–2017 4Runner 4.0L V6 models. Six plugs cover a set replacement, while the listing describes the design as a performance upgrade.

The stated 2014–2017 4.0L V6 fitment gives owners a defined application, and the six-piece pack supports replacing the set together. DENSO combines a tapered-cut U-Groove ground electrode with a 0.4mm iridium tip; the listing also identifies a 360-degree laser-welding assembly. These construction details distinguish the Iridium Power model from DENSO’s long-life set for the same years. The supplied description associates a larger spark with power and fuel economy, but does not quantify either outcome.

Skip it if you have a 2003–2013 4.0L V6; the DENSO Iridium Long Life set B0B7KSHX6Y lists that earlier range.

Owners of a 2014–2017 4.0L V6 4Runner seeking DENSO Iridium Power electrode features can consider this six-pack. The application is specifically bounded by those listed years and engine, rather than earlier 4.0L models.

Listed on Amazon as: 6 pc DENSO Iridium Power Spark Plugs for Toyota 4Runner 4.0L V6 2014-17

#7

7. DENSO Platinum TT Plugs

• Core Material: Platinum
• Top Material Type: Platinum
• Weight: 11.52 oz
• Gap Size: 0.04 in

Best for: Platinum TT for 2003–2013.

Why it ranks #7: The six-plug set is listed for 2003–2013 4.0L V6 4Runners and uses a 1.1 mm platinum center electrode with a titanium-enhanced ground strap.

DENSO Platinum TT pairs a 1.1mm platinum center electrode with a titanium-enhanced ground strap, distinguishing this six-plug set from the iridium choices. The listing specifies 2003–2013 Toyota 4Runner 4.0L V6 models, so its twin-tip design targets a defined generation and engine.

The 1.1mm platinum center electrode and titanium-enhanced ground strap are the defining construction details; DENSO describes the combination as supporting faster starts. Listed compatibility with 2003–2013 4.0L V6 4Runners helps owners identify the intended application, and six plugs provide the quantity for a set change. The Platinum TT design is a relevant alternative for buyers preferring platinum construction over an iridium center electrode. The listing does not specify later 4.0L V6 years.

Skip it if you own a 2014–2017 4.0L V6; the DENSO Iridium Power set B0B7KTJMC3 specifies those years.

This set suits 2003–2013 4.0L V6 4Runner owners who want DENSO Platinum TT construction and its stated electrode combination. Choose with the model-year boundary in mind; later 4.0L V6 fitment is not listed.

Listed on Amazon as: 6 pc DENSO Platinum TT Spark Plugs for Toyota 4Runner 4.0L V6 2003-13

#8

8. DENSO Standard Plugs

• Core Material: Copper
• Top Material Type: Copper
• Weight: 11.52 oz
• Gap Size: 0.04 in

Best for: 1996–2002 3.4L V6 service.

Why it ranks #8: This six-piece copper-plug set specifically lists the 3.4L V6 4Runner from 1996–2002, serving an older and different engine fitment.

DENSO’s larger spark nucleus is the defining feature of this copper-plug six-pack, with the listing linking greater spark energy to more complete flame travel. It is specified for 1996–2002 Toyota 4Runner 3.4L V6 models, giving owners of those earlier trucks a generation-specific replacement option.

The listed 3.4L V6 fitment for 1996–2002 4Runner models makes this set relevant to owners servicing that earlier generation, rather than later 4.0L trucks. DENSO’s ground-electrode design creates a larger spark nucleus, and the supplied description connects greater spark energy with more consistent flame travel and complete combustion. Copper core and top materials distinguish it from the iridium options in this roundup. The six-piece quantity suits a full set change; the listing gives a 0.04-inch gap specification.

Skip it if you have a 2003–2013 4.0L V6; the DENSO Iridium Long Life set B0B7KSHX6Y lists those years.

This copper DENSO set suits owners maintaining a 1996–2002 3.4L V6 4Runner who value its stated ground-electrode ignition design. Its fit boundary is important: the listing does not specify the later 4.0L V6 application.

Listed on Amazon as: 6 pc DENSO Standard Spark Plugs for Toyota 4Runner 3.4L V6 1996-2002

#9

9. DENSO 3417 Iridium Plugs

• Core Material: Iridium
• Top Material Type: Ceramic
• Weight: 11.52 oz

Best for: DENSO 3417 six-piece set.

Why it ranks #9: The product is a genuine six-pack of DENSO 3417 iridium plugs, but its listing does not specify Toyota 4Runner fitment or model years.

DENSO’s SK16HR11 iridium long-life plug is sold here as a six-piece order, making pack quantity its clearest practical distinction. The listing identifies the 3417 number, iridium core, ceramic top, and M14x1.25 thread, giving shoppers concrete component details to compare before selecting plugs.

The six-piece quantity supports planning a complete plug service, while the M14x1.25 thread specification gives a dimensional detail for evaluating the part. DENSO identifies this as an iridium long-life spark plug, so the material and stated service-life positioning are clear. The ceramic top material is another useful component specification, distinct from the iridium core. Crucially for a Toyota 4Runner roundup, the supplied product details do not list a 4Runner year or engine, limiting how confidently buyers can establish vehicle application.

Skip it if you require documented 4Runner fitment; the DENSO Iridium Long Life set B0D1S7ZM7T lists 2014–2017 4.0L V6 models.

The DENSO 3417 suits shoppers comparing a six-piece iridium long-life set with a stated thread size and ceramic top. For a 4Runner repair, treat the missing year and engine fitment information as a material boundary.

Listed on Amazon as: 6 PCS NEW — DENSO # 3417 Iridium LONG LIFE Spark Plugs — SK16HR11

#10

10. NGK 6619 Iridium Plugs

• Core Material: Iridium
• Top Material Type: Iridium
• Weight: 0.27 g

Best for: Six-plug NGK iridium option.

Why it ranks #10: This six-pack offers iridium construction and a wider stated heat range, but the supplied listing does not identify Toyota 4Runner fitment.

A wider operating heat range is the central draw of NGK’s LFR6AIX-11 iridium plugs, which the listing says resist carbon buildup and pre-ignition. Sold as a six-pack, they give buyers seeking these specific NGK characteristics a complete quantity for a multi-plug service.

The wider operating heat range is presented as an advantage over ordinary plugs, while resistance to carbon buildup and pre-ignition addresses two named operating concerns. NGK’s patented triple-gasket sealing process is described as eliminating the possibility of combustion-gas leakage, providing a specific sealing feature alongside the iridium construction. The six-plug pack makes the quantity clear for a set service. However, the supplied listing does not identify Toyota 4Runner years or engine fitment, so buyers cannot establish application from its product details alone.

Skip it if you need listed 4Runner fitment; the NGK Laser Iridium set B0B7LTWTTJ specifies 2013–2020 4.0L V6 models.

This six-pack fits shoppers prioritizing NGK iridium construction, a wider stated heat range, and triple-gasket sealing features. It is a poor choice when the purchase requires a documented 4Runner year and engine application, which this listing does not provide.

Listed on Amazon as: NGK 6619 Iridium Spark Plugs LFR6AIX-11-6 Pack