Best Spark Plugs For 2006 Mustang GT

When I bought my S197, I knew maintenance would be key to keeping that 4.6L Mod Motor running strong. Dealing with frustrating low-end misfires and wanting better throttle response led me down the rabbit hole of finding the absolute best spark plugs for my 2006 Mustang GT. This comprehensive guide is based on digging through OEM standards and aftermarket high-performance options, focusing specifically on plugs that guarantee reliable ignition performance and help restore that classic V8 power.

IMAGE	PRODUCT NAME	AMAZON LINK
	Iridium Spark Plugs 8 Pack SP515 SP546 Compatible with…	View on Amazon
	New Motorcraft SP547 Spark Plug (8 PACK) Finewire Platinum	View on Amazon
	Pack of 8 Genuine Motorcraft Spark Plug SP-493 AGSF32PM	View on Amazon
	A-Premium Iridium Platinum Spark Plugs Compatible with Ford…	View on Amazon
	A-Premium Double Iridium Spark Plug Compatible with Ford…	View on Amazon
	SCITOO Platinum Iridium Spark Plugs 4477 for Ford for…	View on Amazon
	NGK G-Power Spark Plug TR55-1GP (6 Pack) for FORD MUSTANG…	View on Amazon
	GPMMWPG Ignition Coil Pack and Spark Plugs Compatible with…	View on Amazon
	SYKRSS Set of 8 Ignition Coil Pack UF191 and Iridium…	View on Amazon
	A-Premium Iridium Platinum Spark Plugs Compatible with Ford…	View on Amazon

Iridium Spark Plugs 8 Pack SP515 SP546 Compatible with 2004 2005 2006 2007 2008 Ford F150 5.4 Expedition Explorer Mustang F250 F350 F450 & Lincoln Mark LT Navigator & Mercury Mountaineer V8 4.6L 5.4L

If you’re looking for a highly compatible and robust aftermarket solution for your 4.6L V8, this Iridium set is a great choice. These plugs are engineered to tackle common issues like backfiring and poor idling, making them an excellent replacement if you’ve been experiencing sluggish engine performance. The iridium electrode design provides strong, consistent ignition, ensuring your ‘Stang runs smoothly across its entire speed range.

Key features that stand out:

• Reference Number: SP515, SP-515, SP546, SP-546
• Quality Control: Designed to address common ignition system issues like misfiring and poor fuel economy.
• Warranty: Comes with a 12-month worry-free warranty.

Pros:
– High compatibility across many Ford V8 models, including the 2006 Mustang GT.
– Iridium construction offers excellent longevity and reliable spark.
– Targeted at solving common performance issues.

Cons:
– Aftermarket brand means long-term testing data is less established than OEM.

Best for:
Drivers looking for a budget-friendly, high-quality iridium replacement set designed to fix common ignition problems.

Expert Opinion: This set offers solid material quality and wide application, making it a reliable plug-and-play option for routine maintenance where the vehicle hasn’t been heavily modified.

New Motorcraft SP547 Spark Plug (8 PACK) Finewire Platinum

When it comes to the 4.6L V8, many enthusiasts swear by using genuine OEM parts, and Motorcraft is Ford’s trusted original equipment manufacturer. The SP547 Finewire Platinum plugs deliver the exact quality and specifications Ford intended for your 2006 Mustang GT. Choosing Motorcraft means you’re prioritizing reliability and durability that meets factory standards, providing assurance that your engine is getting components designed specifically for it.

Key features that stand out:

• Genuine OEM: Provides the exact quality, reliability, and durability expected from the factory.
• Material: Finewire Platinum construction.
• Reference Number: SP547X PZK1FX.

Pros:
– Guaranteed fit and function straight from the OEM.
– Excellent, tested durability and reliability.
– Minimizes the risk of installation or compatibility issues.

Cons:
– Typically higher priced than comparable aftermarket options.

Best for:
Purists and owners who prioritize factory-level performance, fit, and long-term reliability above all else.

Expert Opinion: You simply can’t go wrong with OEM Motorcraft plugs, especially for the Mod Motor series. They are the gold standard for maintenance and ensuring the 2006 GT maintains factory performance specs.

Pack of 8 Genuine Motorcraft Spark Plug SP-493 AGSF32PM

Another excellent OEM option, the Motorcraft SP-493, is a Platinum plug that delivers reliable ignition performance and superior heat transfer. These plugs are often a preferred replacement for many S197 owners who want to stick with trusted, factory-grade components. If you’re concerned about using non-OEM parts, the SP-493 provides the peace of mind that comes with Genuine Motorcraft quality, ensuring smooth combustion and consistent power delivery.

Key features that stand out:

• Material: Genuine Motorcraft Platinum Spark Plug.
• Packaging: Brand new in the box, ensuring authenticity.
• Reference Number: AGSF32PM.

Pros:
– Proven reliability and longevity in Ford modular engines.
– Easy drop-in installation with exact factory tolerances.
– Excellent value for an OEM platinum plug.

Cons:
– Platinum might not offer the extreme longevity of double iridium designs.

Best for:
Ford enthusiasts seeking reliable, economical OEM platinum performance without sacrificing quality.

Expert Opinion: The SP-493 is a classic, dependable plug. While slightly older technology compared to the SP547, it’s a solid, proven performer for the 4.6L V8 that offers great bang for your buck.

A-Premium Iridium Platinum Spark Plugs Compatible with Ford F-150 1999-2003, Mustang 2003-2004 2007-2012, GT 2005-2006, Crown Victoria 1996-2005, 4.6L 5.4L, Pack of 8

This A-Premium set features a robust Iridium tip and a Platinum core, engineered to provide superior ignitability and extended life. These are designed to minimize wear and tear, allowing for replacement intervals between 80,000 to 100,000 miles, which is fantastic for owners seeking long service life. The precise specifications ensure maximum ignition performance, giving your Mustang a responsive feel.

Key features that stand out:

• Material Combination: Iridium center tip and Platinum core.
• Longevity: Recommended replacement interval of 80,000 to 100,000 miles.
• Gap Size: Available in 0.044/0.054 IN range (check specific factory recommendation before installation).

Pros:
– Outstanding service life due to the premium metal combination.
– Engineered for maximum ignition performance.
– High resistance and durability.

Cons:
– Compatibility listed spans a wide range of model years, requiring careful verification of the 2006 4.6L V8 fitment.

Best for:
Mustang owners prioritizing maximum mileage between changes and excellent durability from a combined Iridium/Platinum plug.

Expert Opinion: The fusion of iridium and platinum materials offers a great balance between high performance and extended maintenance cycles. If you hate changing spark plugs often, these are worth considering.

A-Premium Double Iridium Spark Plug Compatible with Ford Explorer 2006-2008, Explorer Sport Trac 2007-2008, Mustang 2005-2008 & Mercury Mountaineer 2006-2008 & Avanti Avanti, 4.6L, Pack of 8

For owners looking for the cutting edge in spark plug technology, these A-Premium Double Iridium plugs are engineered for exceptional ignitability. With both the center electrode core and tip made of Iridium, these plugs provide an incredibly focused and stable spark. This design translates directly into quicker starts, smoother idle, and potentially better fuel economy for your 2006 Mustang GT 4.6L.

Key features that stand out:

• Material: Double Iridium construction (tip and core).
• Ignition Performance: Engineered for maximum ignition and superior lifespan.
• Fitment Focus: Specifically lists the Mustang 2005-2008 V8 4.6L.

Pros:
– Superior spark stability and reliability thanks to double iridium.
– Excellent longevity (80,000 to 100,000 miles).
– Direct fitment for the 4.6L Mustang V8 model years.

Cons:
– Double iridium can be one of the more expensive materials available.

Best for:
Performance-minded daily drivers who want the benefits of cutting-edge ignition technology and long life.

Expert Opinion: Double iridium is fantastic for maintaining a consistent, powerful spark over vast distances. These plugs are a premium choice if reliability under various driving conditions is your main goal.

SCITOO Platinum Iridium Spark Plugs 4477 for Ford for F-150 1999-2003, for Mustang 2003-2004 2007-2012, GT 2005-2006, Crown Victoria 1996-2005, 4.6L 5.4L Pack of 8

The SCITOO Platinum Iridium plugs are an aftermarket solution designed to match the performance of OEM plugs while offering competitive value. Utilizing iridium for the central electrode, these plugs promote a more stable idle speed and faster engine start-up compared to traditional copper or standard platinum plugs. They emphasize OE design for a straightforward, drop-in installation.

Key features that stand out:

• Function: Ensures reliable high-voltage spark for consistent ignition.
• Material: Platinum Iridium construction for enhanced stability.
• Installation: OE design allows for an easy drop-in fit.

Pros:
– Good balance of price and performance.
– Stable idle speed and quick starting capabilities.
– Direct replacement for common reference numbers (e.g., 4477).

Cons:
– As a budget option, some quality control reports can be inconsistent compared to Motorcraft.

Best for:
The cost-conscious owner needing a reliable, mixed-metal plug replacement without breaking the bank.

Expert Opinion: SCITOO delivers a functional product that meets many standard requirements. Always double-check the plug gap upon receipt to ensure it matches the 2006 Mustang GT specifications for optimal performance.

NGK G-Power Spark Plug TR55-1GP (6 Pack) for FORD MUSTANG BASE 2005-2010 4.0L/245

NGK is a globally respected name in ignition components, and the G-Power series offers excellent features like trivalent metal plating for anti-corrosion. Crucially, please note this specific listing is a 6-pack intended for the 4.0L V6 Mustang base model. While the TR55-1GP is a great fine-wire platinum plug with superior heat transfer and flashover prevention, it is not the correct 8-pack for the 4.6L V8 2006 Mustang GT. We’ve included it here mainly as a reference point for NGK quality, should the V8 equivalent be sought.

Key features that stand out:

• NGK Quality: Trivalent metal plating provides superior anti-corrosion properties.
• Design: Corrugated ribs prevent flashover, and triple seals prevent leakage.
• Material: Fine wire platinum tipped center electrode for superior acceleration.

Pros:
– NGK is renowned for quality and performance.
– Excellent heat management properties.
– Improved fuel economy potential.

Cons:
– This product is specifically for the V6 4.0L engine, not the V8 GT (requires 8 plugs).

Best for:
Owners of the V6 Mustang looking for NGK quality (V8 owners should seek the appropriate 8-pack NGK part number).

Expert Opinion: NGK consistently produces reliable, high-performance plugs. While the TR55-1GP isn’t for the V8, the underlying technology (like the pure alumina silicate ceramic insulator) is excellent.

GPMMWPG Ignition Coil Pack and Spark Plugs Compatible with Ford Mustang 1999-2014, 4.6L 1999-2004, 5.4L 2007-2012, 5.8L 2013-2014, GT 2005-2006, Spark Plugs Coil Packs Replaces# UF191 6708 Set of 8

This comprehensive kit from GPMMWPG offers the advantage of replacing two critical ignition components—the coils and the spark plugs—simultaneously. This is often the best solution if you are troubleshooting stubborn misfires, as both parts tend to wear out together. The plugs are double iridium, paired with high-performance coils featuring upgraded copper windings for a 15% stronger spark energy.

Key features that stand out:

• Complete Kit: Includes both 8 ignition coil packs and 8 iridium spark plugs.
• Performance Upgrade: Delivers up to 15% stronger spark energy for better combustion efficiency.
• Longevity: Double iridium plugs offer up to 100,000 km (approx. 62,000 miles) service life.

Pros:
– One-stop solution for a complete ignition system overhaul.
– Enhanced engine response and driving power.
– Excellent value proposition for replacing both coils and plugs.

Cons:
– If only spark plugs are needed, purchasing the entire kit is unnecessary.

Best for:
Mustang owners performing a full ignition system tune-up to solve persistent misfire or low power issues.

Expert Opinion: Replacing coils when changing plugs on a high-mileage 4.6L V8 is smart preventative maintenance. This kit provides a coordinated upgrade, ensuring the plugs and coils work perfectly together to maximize ignition efficiency.

SYKRSS Set of 8 Ignition Coil Pack UF191 and Iridium Spark Plug SP493 Compatible with Lincoln Navigator Aviator Continental Mark VIII Mustang GT Marauder Panoz Esperante Avanti 4.6L 5.4L 5.8L V8

Similar to the previous entry, the SYKRSS kit provides a complete ignition overhaul, combining 8 quality ignition coils (UF191 replacement) with 8 iridium SP493 replacement spark plugs. This set is specifically designed to meet or exceed OE specifications in form, fit, and function, providing high heat resistance and reliable voltage transfer. It’s an ideal way to restore power and fix common ignition failures like backfiring and poor idling in your 2006 GT.

Key features that stand out:

• OE Standard: Designed to meet or exceed original equipment specifications.
• Material: High heat temperature resistant coil material and iridium plugs.
• Solution: Targeted to fix common issues like misfires, stalling, and engine jerking.
• Warranty: Backed by a generous 24-month warranty.

Pros:
– Complete system replacement for maximum reliability.
– High durability and reliability under stress.
– Excellent 24-month warranty provides strong buyer confidence.

Cons:
– The coil quality might not be as universally trusted as Motorcraft OEM coils.

Best for:
DIYers wanting a full ignition system replacement kit with extended warranty coverage.

Expert Opinion: The use of SP493 (a Motorcraft OEM reference number) implies they are matching a proven plug design. This kit provides excellent value for comprehensive maintenance, provided the coils hold up over time.

A-Premium Iridium Platinum Spark Plugs Compatible with Ford F-150, F-150 Heritage, Mustang, Crown Victoria, GT & Chevrolet Camaro, Corvette & Cadillac CTS & Lincoln Town Car & Mercury, Pack of 8

Here is another versatile Iridium Platinum set from A-Premium, featuring a unique gap size tailored toward performance vehicles. These plugs boast superior longevity, aimed at providing stable performance for 80,000 to 100,000 miles. With a specialized design that crosses into applications for high-performance GM V8s (Camaro/Corvette), these plugs are built to withstand the demands of aggressive driving in your GT.

Key features that stand out:

• Material: Iridium tip paired with a Platinum core.
• Vehicle Fitment: Extremely wide compatibility, including the 2006 Mustang GT 5.4L (and often suitable for the 4.6L).
• Gap Specification: Precise 0.040 IN gap size, which is critical for some high-output applications.

Pros:
– Proven durability and long lifespan.
– Engineered to handle high stress and performance demands.
– Excellent anti-corrosion properties.

Cons:
– You must verify the specific 0.040 IN gap is appropriate for your exact 4.6L engine tune before installation.

Best for:
Owners of high-mileage or lightly modified 2006 GTs seeking durable plugs proven in performance environments.

Expert Opinion: The tighter 0.040-inch gap specification suggests suitability for modified or high-output engines, though the factory spec might be slightly wider. Always check your service manual or tuner recommendations if running aftermarket parts.

Comparison Short Insights

When choosing the right set of Best Spark Plugs For 2006 Mustang GT, you typically face three main choices: OEM, Premium Iridium, or a Coil/Plug Kit.

OEM Reliability: If your Mustang is stock and you want guaranteed fitment and predictable longevity, the Motorcraft SP547 or SP-493 are hard to beat. They meet the exact factory standards Ford engineers designed the 4.6L Mod Motor around.

Longevity and Performance: For maximizing the time between service intervals, look toward the Double Iridium options, such as the A-Premium Double Iridium set. These plugs offer superior erosion resistance and maintain a crisp, strong spark for 80,000+ miles.

Addressing Misfires: If you are actively troubleshooting power loss or misfires, selecting a full replacement Coil and Plug Kit (like the GPMMWPG or SYKRSS sets) provides the most comprehensive solution, as coils often fail around the same time as plugs. This is a great way to ensure the entire ignition system is fresh.

V8 vs. V6 Warning: Always ensure you purchase the 8-pack (for the 4.6L V8 GT) and not the 6-pack (for the 4.0L V6 Base Mustang), a mistake easily made, as highlighted by the NGK TR55-1GP listing.

Final Verdict

Choosing the right spark plug for your 2006 Mustang GT depends on your maintenance goals and budget.

The Top Choice for Factory Feel and Reliability: The New Motorcraft SP547 Spark Plug (8 PACK) Finewire Platinum takes the crown for reliability. While it might not be the highest performing plug available, it ensures your 4.6L V8 is running exactly as Ford intended, eliminating compatibility worries and providing proven durability.

The Best for Extended Life and Performance: If you want premium materials that last far longer than platinum, go for the A-Premium Double Iridium Spark Plug. The double iridium construction guarantees consistent spark quality deep into the 80,000-mile range.

The Smart Upgrade Option: For owners dealing with aging components and possible misfires, the GPMMWPG Ignition Coil Pack and Spark Plugs Compatible Kit offers superior value. Replacing the coils and plugs together is preventative maintenance at its finest and ensures powerful, stable ignition across the board.

Best Spark Plugs For 2006 Mustang GT: Comprehensive FAQ

Q1: What is the factory recommended spark plug gap for the 2006 Mustang GT 4.6L V8 engine?

A: The exact gap specification can vary slightly based on the specific Motorcraft plug used, but generally, the factory gap for the 2006 4.6L V8 Mod Motor is around 0.045 inches. Always confirm this measurement in your vehicle’s owner’s manual or on the OEM plug specifications sheet. It’s always best practice to check and adjust the gap on new plugs before installation.

Q2: Should I use Platinum or Iridium spark plugs in my 2006 Mustang GT?

A: Both are far superior to traditional copper for this engine. Platinum (like the Motorcraft SP-493) offers great heat resistance and lasts around 60,000 miles. Iridium is the newer, stronger material, offering better ignitability and superior resistance to wear, often lasting 80,000 to 100,000 miles. If longevity is key, choose Iridium or Double Iridium.

Q3: How often should I change the spark plugs in my 2006 Mustang GT?

A: For standard factory plugs (Motorcraft Platinum), the recommended interval is typically around 60,000 to 75,000 miles. If you install premium iridium spark plugs, you can usually extend that interval to 80,000 to 100,000 miles. However, if your Mustang is modified or driven aggressively, you should inspect and change them more frequently.

Q4: My 4.6L Mustang is misfiring. Will new spark plugs fix the issue?

A: New spark plugs are the first step in diagnosing and fixing a misfiring issue. If the misfires persist after installing new plugs, the problem is often related to the ignition coils (coil packs) or fuel delivery. Purchasing a full kit that includes both plugs and coils (like the GPMMWPG set) is a proactive way to address both potential failure points simultaneously.

Q5: Is it safe to use aftermarket spark plugs instead of Motorcraft OEM plugs?

A: Yes, it is safe, provided the aftermarket plugs meet or exceed the OE specifications for heat range, thread size, and material quality. Reputable brands like NGK, SCITOO, and A-Premium offer high-quality plugs that perform well or even better than OEM, particularly in terms of longevity (due to the use of Double Iridium). Just ensure the plug reference numbers match the required application.

Q6: Do I need to gap iridium spark plugs myself, or do they come pre-gapped?

A: While most high-quality iridium plugs, especially those for the 2006 Mustang GT, are advertised as “pre-gapped,” you should always double-check the gap measurement before installation. Transport and handling can sometimes cause the gap to shift, and installing an improperly gapped plug can cause immediate performance issues and damage the electrode.