Best Spark Plugs For Toyota Highlander

#1 · Best Overall

1. NGK Iridium IX

• Core Material: Iridium
• Top Material Type: Metal
• Compatible with Vehicle Type: Car

Best for: 2008–2016 V6 Iridium Replacement.

Why it ranks #1: This six-plug iridium set explicitly fits the 3.5L V6 Highlander application listed, and includes original packaging and hardware.

A six-plug NGK Iridium IX set is listed specifically for 2008–2016 Toyota Highlander 3.5L V6 models, giving owners a complete set of genuine NGK replacement plugs in one purchase. Its iridium core and stated 0.04-inch gap distinguish this option for buyers seeking a direct-replacement set.

The vehicle-specific 3.5L V6 year range helps shoppers narrow the choice to the listed Highlander application, while the six-piece quantity supplies a full set for that engine. NGK identifies the plugs as genuine parts and direct replacements, supporting a familiar replacement workflow; original packaging and hardware are also included. The listed iridium core and 0.04-inch gap provide concrete specifications to compare with service requirements, but the listing directs buyers to confirm vehicle fitment.

Skip it if you own a 2001–2010 3.0L or 3.3L V6 Highlander; the NGK V-Power set is listed for those engines instead.

Choose this set if your Highlander is a listed 2008–2016 3.5L V6 and you want six NGK iridium direct replacements. Check the vehicle application and gap against your engine's requirements before installation.

Listed on Amazon as: 6 pc NGK Iridium IX Spark Plugs for Toyota Highlander 3.5L V6 2008-16

#2 · Long-Life Iridium

2. DENSO Iridium Long Life

Best for: Long-Life 2008–2016 V6 Plugs.

Why it ranks #2: The six-plug set is listed for the 3.5L V6 application and specifies a fine-wire 0.4mm iridium center electrode.

DENSO Iridium Long Life combines a fine-wire 0.4 mm iridium center electrode with a platinum ground strap, a specific electrode pairing for the listed Highlander 3.5L V6. The six-plug set covers 2008–2016 models, and the listing identifies DENSO as an OE manufacturer.

The fine-wire 0.4 mm iridium center electrode and platinum ground strap give buyers two concrete construction details associated with this Long Life plug. DENSO describes a larger spark as translating to more power and superior fuel economy, though the listing does not quantify either result. Six genuine DENSO plugs cover the stated 2008–2016 3.5L V6 application, while the fit description specifies a 0.044-inch gap for comparison with vehicle service requirements.

Skip it if you own a 2017–2020 3.5L V6 Highlander; the Sixity Auto Champion Iridium set lists those years.

Choose these DENSO Long Life plugs if your Highlander is a listed 2008–2016 3.5L V6 and you want the iridium-and-platinum electrode combination. The stated fit range does not extend to newer model years.

Listed on Amazon as: 6 pc DENSO Iridium Long Life Spark Plugs for Toyota Highlander 2008-16

#3 · Fine-Wire Electrode

3. DENSO Iridium Power

• Core Material: Iridium
• Top Material Type: Nickel
• Compatible with Vehicle Type: Car, Truck
• Thread Size: 14mm x 1.25

Best for: 2008–2016 V6 Performance Focus.

Why it ranks #3: This six-plug 3.5L V6 set specifies a 0.4mm iridium tip, tapered cut, and U-Groove ground electrode.

DENSO's 0.4 mm iridium center electrode and tapered-tip design give this six-plug set a specific performance-focused distinction for listed 2008–2016 Highlander 3.5L V6 models. Its U-Groove ground electrode is another stated design feature, while the listing describes a larger spark as supporting power and fuel economy.

The 0.4 mm iridium tip and tapered cut put the design emphasis on the spark electrode, while the patented U-Groove ground electrode provides another named feature for buyers comparing plug construction. DENSO states that a larger spark translates to more power and superior fuel economy, framing the intended operating benefit without guaranteeing a result. Six genuine DENSO plugs cover the listed 3.5L V6 application; the listing gives a 0.044-inch gap in its fit description.

Skip it if you need plugs for a 2017–2020 3.5L V6 Highlander; the Champion Iridium set lists those model years.

This set suits owners of a listed 2008–2016 3.5L V6 Highlander who want DENSO Iridium Power construction and its fine 0.4 mm tip. Verify the application and specified gap before fitting.

Listed on Amazon as: 6 pc DENSO Iridium Power Spark Plugs for Toyota Highlander 3.5L V6 2008-16

#4 · Broadest V6 Range

4. E3 DiamondFIRE

Best for: Broad-Year 3.5L V6 Coverage.

Why it ranks #4: Its six-plug set lists 3.5L V6 Highlander compatibility across the broadest stated model-year range in this selection.

E3 lists this six-plug set for Highlander 3.5L V6 models from 2008 through 2022, extending its stated coverage beyond several narrower year ranges. Its DiamondFIRE edge-to-edge spark path is described as replenishing the spark zone with a fresh charge, a defining feature for buyers comparing plug designs.

The broad listed 2008–2022 3.5L V6 range can simplify selection for owners whose model year falls within that span, and six plugs provide a set for the stated engine. E3's DiamondFIRE design uses an edge-to-edge spark path that the listing says allows the spark zone to be replenished with a fresh charge. A resistor is included to reduce electromagnetic interference, while the gasket seat is also stated in the feature description.

Skip it if you need a stated iridium core and gap; the Sixity Auto NGK Iridium IX listing provides both for 2008–2016 3.5L V6 models.

This E3 set fits buyers seeking the listed 2008–2022 Highlander 3.5L V6 range and its DiamondFIRE features. Check the vehicle's required plug specifications, since the supplied details do not state core material or gap.

Listed on Amazon as: 6 pc E3 Spark Plugs compatible with Toyota Highlander 3.5L V6 2008-2022

#5

5. Champion Iridium

Best for: 2017–2020 3.5L V6 Owners.

Why it ranks #5: This six-plug iridium set is listed for the 3.5L V6 Highlander application, with a stated 0.031-inch gap.

Champion lists this six-plug iridium set for Highlander 3.5L V6 models from 2017–2020, addressing a newer year range than several older-engine options. The supplied fit details name plug type REC10WMPB and a 0.031-inch gap, useful specifics for comparing the listed application.

The 2017–2020 Highlander 3.5L V6 fit range and six-plug quantity identify the intended vehicle group and provide a set for that engine. Champion describes its ignition parts as keeping engines running at their best and its plugs as using durable precious metals for long-lasting, powerful performance. The listing specifies REC10WMPB and a 0.031-inch gap, giving buyers additional fit details to compare with their vehicle's requirements before installation.

Skip it if you drive a 2008–2016 3.5L V6 Highlander; the Sixity Auto DENSO Iridium Long Life set lists that year range.

This Champion set suits owners of a listed 2017–2020 Highlander 3.5L V6 who want iridium plugs with a stated plug type and gap. Its supplied fit range does not include other model years.

Listed on Amazon as: 6 pc Champion Iridium Spark Plugs for Toyota Highlander 3.5L V6 2017-20

#6

6. NGK Laser Iridium

• Core Material: Iridium
• Top Material Type: Ceramic, Metal
• Compatible with Vehicle Type: Car, Truck
• Thread Size: 0.044 in

Best for: Older V6 NGK Iridium Set.

Why it ranks #6: The six-plug set explicitly fits listed 3.0L and 3.3L V6 Highlander applications and uses an iridium core.

NGK Laser Iridium provides a six-plug set listed for Highlander 3.0L and 3.3L V6 models from 2001–2010, bringing an iridium-core option to those older engines. Genuine NGK parts, original packaging, and hardware are included, and the listing identifies them as direct replacements.

The stated 2001–2010 3.0L and 3.3L V6 coverage helps owners identify the listed engine application, while six plugs provide a complete set for that configuration. NGK identifies the parts as genuine direct replacements and includes original packaging and hardware, supporting a conventional replacement workflow. The iridium core is a clear material specification; the listing gives a 0.04-inch gap, which buyers can compare with their vehicle's service requirements.

Skip it if you own a 2001–2007 2.4L L4 Highlander; the Sixity Auto DENSO Platinum TT four-pack lists that engine.

This NGK set suits owners of a listed 2001–2010 Highlander 3.0L or 3.3L V6 who want iridium direct replacements. Check that engine and gap details match your vehicle before installation.

Listed on Amazon as: 6 pc NGK Laser Iridium Spark Plugs for Toyota Highlander 2001-10

#7

7. NGK V-Power

• Core Material: Copper
• Top Material Type: Ceramic, Metal
• Compatible with Vehicle Type: Car, Truck
• Thread Size: 10×1.25mm

Best for: Older V6 Copper Replacement.

Why it ranks #7: This six-plug copper-core set is listed for 3.0L and 3.3L V6 Highlanders and includes original packaging and hardware.

A copper-core NGK V-Power set is listed for Highlander 3.0L and 3.3L V6 models from 2001–2010, making its engine and year range the key distinction. Six genuine plugs, original packaging, and hardware provide a complete replacement set for the listed application.

The 3.0L and 3.3L V6 application covers the older Highlander engines identified in the listing, while six plugs supply a full engine set. NGK identifies these as genuine V-Power direct-replacement parts, and original packaging and hardware are included, supporting a straightforward replacement workflow. The copper core and stated 0.04-inch gap give buyers material and gap details to compare with service specifications; the listing also gives a 10×1.25 mm thread size.

Skip it if you have a 2001–2010 3.0L or 3.3L V6 but prefer platinum; DENSO Platinum TT is listed for those engines.

Choose this NGK V-Power set for a listed 2001–2010 Highlander 3.0L or 3.3L V6 when copper-core plugs suit your requirements. Its stated application does not cover the 2.4L L4.

Listed on Amazon as: 6 pc NGK V-Power Spark Plugs for Toyota Highlander 3.0L 3.3L V6 2001-10

#8

8. DENSO Platinum TT V6

• Core Material: Platinum
• Top Material Type: Platinum
• Compatible with Vehicle Type: Car, Truck
• Thread Size: M14x1.25

Best for: Older V6 Platinum TT Set.

Why it ranks #8: Its six-plug platinum set is listed for 3.0L and 3.3L V6 Highlanders and specifies twin-tip technology.

DENSO Platinum TT is listed for Highlander 3.0L and 3.3L V6 models from 2001–2010, with Twin-Tip Technology pairing a platinum center electrode and titanium-enhanced ground strap. Six plugs make this a full set for the listed older V6 application.

The 1.1 mm platinum center electrode and titanium-enhanced ground strap are the defining Platinum TT construction details, giving buyers a specific alternative to copper- or iridium-core listings. DENSO associates its Platinum TT design with faster starts, while its broader description says a larger spark translates to more power and superior fuel economy. Six plugs cover the named 3.0L and 3.3L V6 application, and the fit description states a 0.040-inch gap.

Skip it if you have a 2001–2010 3.0L or 3.3L V6 and want NGK copper plugs; the NGK V-Power set lists those engines.

Consider this DENSO set for a listed 2001–2010 Highlander 3.0L or 3.3L V6 when Platinum TT construction suits your replacement needs. It is not the listed choice for the 2.4L L4.

Listed on Amazon as: 6 pc DENSO Platinum TT Spark Plugs for Toyota Highlander 2001-10

#9

9. DENSO Platinum TT L4

• Core Material: Platinum
• Top Material Type: Platinum
• Compatible with Vehicle Type: Car, Truck
• Thread Size: 0.04

Best for: 2001–2007 L4 Platinum Plugs.

Why it ranks #9: This four-plug platinum set targets the narrower 2.4L L4 Highlander application, rather than the V6 applications covered by most entries.

This four-plug DENSO Platinum TT set is specifically listed for Highlander 2.4L L4 models from 2001–2007, unlike the six-plug V6 applications in this roundup. Its platinum center electrode and titanium-enhanced ground strap define the twin-tip design for this smaller-engine fit.

The 2.4L L4 application and four-plug quantity make this listing relevant to the specified Highlander configuration rather than the V6 models. DENSO's Platinum TT design pairs a 1.1 mm platinum center electrode with a titanium-enhanced alloy ground strap, features associated in the listing with faster starts and a larger spark. The stated 0.040-inch gap supplies another comparison point for checking the plug against the vehicle's service requirements.

Skip it if you have a 2001–2010 3.0L or 3.3L V6 Highlander; the Sixity Auto DENSO Platinum TT six-pack lists those engines.

Choose this set for a listed 2001–2007 Highlander 2.4L L4 when you want DENSO Platinum TT construction in a four-plug quantity. Its stated application does not cover the V6.

Listed on Amazon as: 4 pc DENSO Platinum TT Spark Plugs for Toyota Highlander 2.4L L4 2001-07

#10

10. NGK 6619 Iridium

• Core Material: Iridium
• Top Material Type: Iridium
• Compatible with Vehicle Type: Car, Truck
• Thread Size: 14mm (Thread Diameter), 1.25mm (Thread Pitch)

Best for: Wide-Heat-Range Iridium Buyers.

Why it ranks #10: It is a six-pack of iridium plugs with a 14mm thread, but the listing does not specify Highlander fitment or engine compatibility.

NGK specifies a wider operating heat range than ordinary plugs for these Iridium Spark Plugs, pairing that feature with resistance to carbon buildup and pre-ignition. The six-pack format and 14 mm thread diameter with 1.25 mm pitch offer useful details for buyers comparing replacement-plug specifications.

NGK says the wider heat range and resistance to carbon buildup and pre-ignition are intended to support operation under varied conditions, making these features relevant to buyers focused on plug behavior. A patented triple-gasket sealing process is stated to eliminate the possibility of combustion-gas leakage, addressing sealing directly. The listing supplies a 14 mm thread diameter and 1.25 mm pitch, but does not identify a Highlander engine or model-year fitment, so application matching remains essential.

Skip it if you want an explicitly listed Highlander fit; the Sixity Auto NGK Iridium IX set names 2008–2016 3.5L V6 models.

Consider these NGK plugs if their thread dimensions and operating features match your vehicle's requirements. The listing does not establish Highlander fitment, so buyers needing a confirmed engine-specific application should choose a specifically listed set.

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