Buyers Guide & Information

Best Spark Plugs for Mustang v6 Reviewed

We have reviewed and compared the best spark plugs for Mustang v6. These brands are the top solutions for Ford Mustang engines.

Your Ford Mustang is a muscle car that deserves plenty of attention. With the powerful engines under the hood, you want to find the best spark plugs for a Mustang V6 for your next tune-up.

Our complete review of the top Mustang spark plugs helps you find the model that suits your needs and your budget.


Preview

Product

Compatible Mustangs

Plug Number

Gap Size

Check Price

Bosch9660Double Iridium OE Replacement Spark...

Bosch Automotive 9660

2005-2010 Ford Mustang 4.0L V6

9660

0.040”

NGK (6945) UR45 Spark Plug - Pack of 4

NGK (6945) UR45

1979-1995 Ford Mustang 5.0L

6945

0.046”

8 PCS NEW -- NGK 3403 G-Power Platinum Alloy...

NGK 3403 G-Power TR55GP

1991-2004 Ford Mustang

3403

0.060”

NGK 3951 V-Power Spark Plug - TR-55, 1 Pack

NGK TR55 V-Power

1993-2004 Ford Mustang

TR55

0.060”

Motorcraft SP-520 Spark Plug

Motorcraft

SP-520

2011-2017 Ford Mustang

SP-520

0.051”

The Benefits of Replacing Mustang Spark Plugs

The best Mustang spark plugs are essential to keeping the car’s engine running properly. When your plugs are fouled or contaminated, it’s time to replace them. By upgrading these essential components and the Mustang spark plug wires, you ensure that the motor continues running as it should.

You also maximize the maintenance intervals, improve fuel efficiency, add performance, and significantly eliminate the chances of engine failure. If the engine performance begins to suffer, it might be time to consider a tune-up.


Buyers Guide to Choosing Mustang Spark Plugs

Vehicle Compatibility

If you are in need of 2006 Mustang GT spark plugs, it won’t do you any good to perform a 2011 Mustang V6 spark plug change. Purchase the spark plugs based on the model year and trim level to ensure it fits your vehicle. You also need to consider what engine is located under the hood, or the plugs might not run correctly.

Spark Plug Type & Coating

Many older vehicles are equipped with copper spark plugs. While these work fine, the service life isn’t as long as other options, requiring more frequent changes. Instead, consider upgrading to either platinum or iridium spark plugs, which extend the service life and add more performance. However, the higher-end options will cost more money.

Stock vs. OEM

Sure, you could easily purchase stock 2005 Mustang GT spark plugs, but the quality probably isn’t as good as aftermarket options. OEM plugs contain materials that are lower grade. Plus, the insulators tend to be more fragile, which shortens the service life. While you will spend more to upgrade, the performance you receive is often worth it.

Build Quality & Heat Range

Spark plug insulation is important to consider. The insulation offers stability to the center electrode. The upper portion extends above the cylinder head, making it more accessible, while the bottom portion supports the center electrode where the heat range is controlled. The spark plug heat range talks about the length of the insulator sections and service area, which determines whether the plug is considered “hot” or “cold.”

Gap Style & Thread Size

You must choose a spark plug that fits your engine’s cylinders perfectly. To do this, you must consider both the thread size and gap. Most modern spark plugs come pre-gapped to work with your vehicle right out of the box, but it’s always wise to check the measurements with a high-quality spark plug gap tool. The 2005 Ford Mustang V6 spark plug gap might be completely different from the 2001 Mustang V6 spark plug gap, so check the owner’s manual before doing a replacement.

Lifespan & Warranty

You don’t want to change your spark plugs often, which is why you should look for a style that lasts longer. Yes, you might pay more upfront, but the cost is often worth the extra time you can spend on the road. Additionally, it’s best to look for a company that provides a lengthy warranty, just in case.

Price

You want to receive maximum 2006 Mustang GT spark plug torque from your purchase, but we also understand the importance of keeping the cost down. To find the best value for your money, take the cost, and divide it by the service life to determine the price-per-mile. You might find that the more expensive options are the best in terms of value. 


5 Best Spark Plugs for Mustang V6 Engines Reviewed

1. Bosch Automotive 9660

Best Spark Plugs for Mustang V6

Compatible Mustangs

2005-2010 Ford Mustang 4.0L V6

Plug Material Coating

Iridium

Top Material

Iridium

Plug Type/Number

9660

Gap Size

0.040”

Your Mustang deserves the best, and Bosch is one brand that provides just that. These double iridium spark plugs feature a well-made ground electrode and firing pin to provide four times the service life compared with OEM copper plugs. With the 0.6mm fine wire firing pin, you get a performance increase and should notice better ignitability.

Plus, Bosch constructs these plugs with a 360-degree continuous laser weld, which fuses the firing pin to the base for exceptional durability. All of these plugs come pre-gapped, ready to install in your Mustang. You won’t need to change these often, as they are made to last. Plus, the company provides a seven-year performance satisfaction guarantee, just in case they don’t live up to your standards.

Buy a one or four-pack, based on what your needs are. However, you must expect a higher bill with these plugs. You are going to spend more than if you choose copper plugs. But, the performance you receive plus the longer changing interval makes this an exceptional value if you don’t mind spending more upfront.

The only thing you’ll have left to figure out is what to do with all of that extra time you have between tune-ups.

Pros

  • Long service life
  • 7-year satisfaction guarantee
  • Double iridium construction
  • Laser weld construction

Cons

  • Expensive

2. NGK (6945) UR45

Best Spark Plugs for 5.0 Mustang

Compatible Mustangs

1979-1995 Ford Mustang 5.0L

Plug Material Coating

Copper

Top Material

Nickel alloy

Plug Type/Number

6945

Gap Size

0.046”

If you are more concerned about value, you want this economical set from NGK. Sure, they don’t include an iridium construction, so you will have to perform your tune-ups more often, but you can save a lot of dough up front. The V-Power spark plugs include V-Groove technology, which is unique to this manufacturer. You can expect better ignitability, prevention against fouling, and improved performance for your precious Ford Mustang.

Even though these aren’t the top-of-the-line option, you can still depend on protection from chemical and electrical wear. That’s what makes them longer-lasting than your standard set of copper spark plugs. With the spark occurring near the edge of the center electrode, the plugs don’t absorb any of the heat until it reaches the electrode. This design allows the flame kernel to expand efficiently and quickly for a more complete burn.

NGK is a leader in automotive equipment and can be trusted with your Mustang engine. The customer reviews speak for themselves, proving that you shouldn’t have any problem. However, if you do, the company only provides a 60-day warranty, which is far shorter than most other brands. Thankfully, there’s no reason to assume you would need to file a claim.

Pros

  • Durable construction
  • Highly rated
  • Increase performance
  • Good value

Cons

  • Only 60-day warranty

3. NGK 3403 G-Power TR55GP

Best Spark Plugs for 4.6 Mustang

Compatible Mustangs

1991-2004 Ford Mustang

Plug Material Coating

Platinum

Top Material

Copper

Plug Type/Number

3403

Gap Size

0.060”

With platinum spark plugs for your Mustang, you can have the perfect combination of performance and value. The G-Power Platinum plugs offer the power you are dreaming of, without breaking the bank. Plus, they are constructed from durable materials, ensuring that you get a longer service life. In fact, the fine pure-platinum electrode tip is unchanged throughout the miles and performs self-cleaning procedures at certain temperatures.

With this set of spark plugs, you can count on better starts, an improvement to your fuel economy and faster acceleration. When you want to install NGK G-Power spark plugs in your Mustang, count on the many others that have already tested and proved the performance. This brand is a top choice among street racers, professional racing teams, and auto enthusiasts worldwide. 

Even though it is an economical choice, you won’t notice any decrease in five-star reviews from customers. Other Mustang owners have been pleased with the performance and service life. The only downside is the company’s warranty policy.

This manufacturer only extends a 60-day guarantee, which isn’t as much protection as we think should be offered. Still, you can’t go wrong if you want to perform your own Mustang tune-up at a decent price.

Pros

  • Highly rated
  • Superior performance
  • Durable construction
  • Good value

Cons

  • Only 60-day warranty

4. NGK TR55 V-Power

Best Cheap Mustang V6 Spark Plug

Compatible Mustangs

1993-2004 Ford Mustang

Plug Material Coating

Copper

Top Material

Nickel

Plug Type/Number

TR55

Gap Size

0.060”

NGK is a top choice because the company provides options like this, offering superior performance and cost-effective plugs. This economical spark plug set is made from copper, but there are many additions that make them better than the OEM plugs in your Mustang. First, the V-Power plugs come with V-Groove technology that you can't find elsewhere. This design offers better ignitability, improved performance, and protection from fouling.

Furthermore, NGK provides additional protection from electrical or chemical wear to ensure these plugs last as long as possible. You should be able to get more miles from them than your typical copper spark plug set. The company also ensures that the spark happens at the edge of the center electrode, so there is no absorption of heat until it gets to the end of the electrode. With this design, the flame kernel expands efficiently and burns more completely.

If you want the best for your Mustang, it's essential to choose an industry leader. Your Mustang engine deserves more protection, which is what NGK strives to provide. Just take a look at the exceptional customer reviews proving that you will get the performance you are looking for. However, as with the other NGK plugs we reviewed, you only get a 60-day warranty, which is shorter than we like.

Pros

  • Economical
  • Improved performance
  • Durable design
  • Highly rated

Cons

  • Only 60-day warranty

5. Motorcraft SP-520

Highly Rated

Compatible Mustangs

2011-2017 Ford Mustang

Plug Material Coating

Platinum

Top Material

Platinum

Plug Type/Number

SP-520

Gap Size

0.051”

Motorcraft is the company that specifically creates Ford parts. Because of this, you can trust the brand to make the spark plugs your Mustang requires. While the company offers plenty of OEM replacements, this spark plug offers a significant upgrade from stock equipment. The fine-wire double platinum spark plug provides better performance and more durability.

Plus, Motorcraft takes it a step further. Instead of just using platinum materials, an iridium-enhanced center electrode is included, which improves the wear resistance and provides more durability. Even with that construction, you aren't paying an expensive price. You shouldn't have to change these spark plugs until you reach 100,000 miles, which allows you more time to enjoy your Ford Mustang without maintenance concerns. 

Now, there's no question that some of the other manufacturers create a more durable and better-performing spark plug. However, there's no reason to overlook Motorcraft as customers love the performance received.

If you read through some of the reviews, you will see that the only recent complaint has been some shipment troubles, which could happen with any spark plug. Plus, the company provides a one-year warranty for even more protection. Trust the leader in Ford parts with your Mustang engine.

Pros

  • Reasonable price
  • 1-year warranty
  • Double platinum
  • Iridium-enhanced center electrode

Cons

  • Shipment issues

Overview of the Mustang V6 Engines & Spark Plugs

The Ford Mustang has been in production since 1964 and has included various engines throughout the years, including a 4.6- and 5.0-liter V8.

Throughout the years, you could have chosen any number of powertrain configurations with an automatic or standard transmission, various horsepower specs, and a V6 gasoline engine. The Mustang V6 requires six spark plugs for replacement, one for each cylinder.


How to Change Spark Plugs on a Mustang V6

If you want to reduce the tune-up cost, consider performing your own 2007 Mustang spark plug removal. Here are some general tips if you want to know how to change spark plugs on Mustang V6 models.

  1. 1
    Locate the spark plugs under the hood. Each model might be different, but you shouldn’t have trouble finding a 2004 Ford Mustang spark plug wiring diagram, 2001 Ford Mustang spark plug wiring diagram, or other specifications you need.
  2. 2
    Clean the area with compressed air. You don’t want any dirt or debris getting into the engine.
  3. 3
    Remove one spark plug at a time and replace it with a new one. You should always check the gap before installation.
  4. 4
    Test drive the vehicle to ensure everything is right.

We also have a helpful video that shows a 2007 Mustang GT spark plug replacement.


People Also Ask (FAQs)

How much horsepower do spark plugs add?

In most situations, you will only see a five to ten horsepower gain from replacing your spark plugs. If you want more performance, consider adding an engine tuner too.

How often should spark plugs be replaced on a Mustang?

It depends on what type of spark plugs you are using and the model you drive. For the most part, you will have to replace spark plugs every 30,000 to 100,000 miles. Check the owner’s manual and read the recommendation from the plug manufacturer.

How many spark plugs does a Mustang V6 need

The Mustang with a V6 engine has six cylinders, which means it requires six spark plugs to perform a complete tune-up, one for each cylinder.

What is the main difference between cheap vs. expensive Mustang spark plugs?

The biggest difference between a cheap and expensive set of spark plugs for your Mustang is the quality. Low-cost options are made with cheap materials that don’t last as long or provide as much protection. It’s often best to invest in higher-quality spark plugs to protect the V6 engine.

Where is the best place to buy replacement spark plugs for a Ford Mustang?

No matter what Mustang accessories and parts you are looking for, it's best to shop with Amazon. The site provides a garage tool that ensures compatibility, and you can find an extensive selection of options.


Conclusion

What are the best spark plugs for a Mustang V6 engine? We are fond of the Bosch Automotive 9660 because of the double iridium design that provides maximum protection and the longest service life.

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