1966 GMC I2500 Spark Plugs

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Keep Your 1966 GMC I2500 in Top Shape with Quality Spark Plugs

Whether you’re repairing or upgrading your Spark Plug, using high-quality parts is key to keeping your 1966 GMC I2500 looking sharp and performing at its best. At Advance Auto Parts we carry a wide selection of dependable options, including Spark Plugs. Whether you’re replacing a damaged part or enhancing your truck’s style and protection, you’ll find exactly what you need to get the job done right.

Top-Rated Spark Plugs from Trusted Brands

Looking for a reliable Spark Plug? We’ve got you covered with options from brands you know and trust like Autolite, Champion, and ACDelco. For example, Autolite Spark Plugs start at just $4.49 with an average 4.6 star rating. Champion and ACDelco offer similar pricing and quality, backed by strong customer feedback. With over 158 reviews and a solid 4.8 star average, you can shop with confidence knowing other GMC I2500 owners approve.

Competitive Prices and Extensive Inventory

The average price for a 1966 GMC I2500 Spark Plug at Advance Auto Parts is around $6.41, with a range that starts at $4.49 and goes up to $8.49. With 9 options in stock from 5 trusted brands, finding the right fit is easy. Popular picks like DiamondFire Spark Plug (E3.46): Enhanced Power & Fuel Efficiency, Champion Copper Plus Spark Plug RN14YC – Dependable Performance & Durability, 405, and ACDelco RAPIDFIRE Spark Plug, 4 start at just $5.99 and offer a great balance of form and function.

Explore Related Parts

While you’re upgrading or replacing your Spark Plug, don’t forget to check out other key components like Distributors and Ignition Coils and Boots. At Advance Auto Parts, we’re here to help you keep your 1966 GMC I2500 in peak condition, inside and out.

Essential 1966 GMC I2500 Spark Plugs

ACDelco – ACDelco Conventional Spark Plug: Reliable Performance & Durability, R44XL (Part No.R44XL)

ACDelco Conventional Spark Plug: Reliable Performance & Durability, R44XL

from

$5.49
ACDelco Professional Conventional Spark Plugs are designed for reliability and efficient performance, and are a high quality replacement for many vehicles on the road today. Their high-quality copper cores and outstanding suppression characteristics deliver reliable performance. They are also available for Marine applications. These premium aftermarket replacement spark plugs are manufactured to meet your expectations for fit, form, and function.
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Champion – Champion Copper Plus Spark Plug RN14YC – Dependable Performance & Durability, 405 (Part No.405)

Champion Copper Plus Spark Plug RN14YC - Dependable Performance & Durability, 405

from

$5.99
Champion Copper Plus spark plugs deliver dependable ignition performance with proven copper-core technology. The copper core electrode provides excellent conductivity and optimized heat control for consistent sparks while the coated shell protects against corrosion. Champion your engine with spark plugs engineered to improve efficiency and keep your vehicle running at its best.
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ACDelco – ACDelco RAPIDFIRE Spark Plug, 4 (Part No.4)

ACDelco RAPIDFIRE Spark Plug, 4

from

$7.99
ACDelco Gold (Professional) RAPIDFIRE Spark Plugs are a high quality alternative to Original Equipment (OE) parts. These RAPIDFIRE Single Platinum Performance Spark Plugs are designed for everyday use and are a high quality replacement for many vehicles on the road today. These premium aftermarket spark plugs have high-quality suppressors that help prevent misfiring, an improved plug to boot seal, and a pure copper core for greater durability. These premium aftermarket replacement spark plugs are manufactured to meet your expectations for fit, form, and function. ACDelco Gold (Professional) parts are manufactured to meet your expectations for fit, form, and function, making them a smart choice for General Motors vehicles, as well as most makes and models, including special applications. These high-quality parts are backed by General Motors. Some ACDelco Gold parts may have formerly appeared as ACDelco Professional.
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Autolite – Autolite Platinum Spark Plug: Enhanced Durability & Improved Performance, AP65 (Part No.AP65)

Autolite Platinum Spark Plug: Enhanced Durability & Improved Performance, AP65

from

$5.49
Platinum Spark Plug: Enhanced Durability & Improved Performance is crafted with a platinum center electrode firing tip that ensures quicker firing, smoother starts, and better acceleration while boosting fuel efficiency. Engineered with a platinum firing tip to prevent gap erosion, it offers a longer service life, making it ideal for older engine applications. The high alumina ceramic insulator enhances thermal conductivity and insulation, providing superior strength, while the multi-rib design prevents flash-over for reliable performance. Its nickel-plated shell resists corrosion, ensuring extended durability even in demanding conditions. Featuring a mid-projection standard center electrode design and a flat seat type, this performance-grade spark plug is backed by over 100 years of engineering expertise and a legacy of more than 11 billion plugs sold. Designed in the USA, it combines advanced materials like platinum and nickel to deliver consistent reliability and value for your vehicle.
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Champion – Champion Platinum Power Spark Plug RN14PMC – Powerful Performance & Longevity, 3405 (Part No.3405)

Champion Platinum Power Spark Plug RN14PMC - Powerful Performance & Longevity, 3405

from

$5.99
Champion Platinum Power spark plugs deliver powerful performance with the exclusive Premium alloy that reaches and sustains the correct operating temperature. A fine-wire center electrode and V-trimmed ground electrode provides sharp spark focus and reliable ignition for consistent combustion under demanding conditions. Champion your engine with spark plugs engineered to improve efficiency and keep your vehicle running at its best.
See More

Motorcraft – Motorcraft Spark Plug: Reliable Ignition for Optimal Engine Performance, SP-416-X (Part No.SP-416-X)

Motorcraft Spark Plug: Reliable Ignition for Optimal Engine Performance, SP-416-X

from

$7.29
Ensure your engine runs smoothly and efficiently with this high-quality spark plug, designed to deliver reliable ignition and optimal performance. Engineered for durability and precision, it provides consistent spark energy to maximize fuel combustion, improving both power output and fuel efficiency. Built to withstand extreme temperatures and pressures, this spark plug ensures long-lasting performance, reducing the need for frequent replacements. Its compatibility with a wide range of vehicles makes it a versatile choice for maintaining peak engine functionality. Whether you’re looking to restore lost performance or maintain your vehicle’s reliability, this spark plug offers exceptional value and dependable operation.
See More

Autolite – Autolite Copper Resistor Spark Plug: Quick Starts & Improved Fuel Efficiency, 405 (Part No.405)

Autolite Copper Resistor Spark Plug: Quick Starts & Improved Fuel Efficiency, 405

from

$4.49
Autolite Copper spark plugs are expertly crafted to ensure quick starts and reliable performance for your vehicle or application. Featuring a copper core center electrode, these spark plugs excel in thermal control and resist fouling, while the high nickel alloy center and ground electrode deliver extended life and durability. The high alumina multi-rib ceramic insulator enhances thermal conductivity and insulation, providing superior strength under demanding conditions. With a nickel-plated shell, these spark plugs are corrosion-resistant, ensuring long-lasting durability. Designed to optimize fuel combustion, they improve fuel efficiency, helping you save money at the pump. Additionally, their advanced engineering promotes smoother and more responsive acceleration, enhancing your driving experience. With a standard center electrode design and short projection, these spark plugs are built for regular-grade applications, making them a reliable choice for maintaining peak engine performance.
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Autolite – Autolite Double Platinum Spark Plug: Enhanced Durability & Performance, APP65 (Part No.APP65)

Autolite Double Platinum Spark Plug: Enhanced Durability & Performance, APP65

from

$7.49
Double Platinum Spark Plug offers enhanced durability and performance with its platinum-to-platinum design, effectively reducing gap erosion and minimizing misfires for a longer service life. Engineered for distributor-less ignition system (DIS) engines, it outperforms copper and standard platinum plugs. The yttrium-enhanced ground electrode ensures superior heat transfer, maintaining durability under high temperatures and pressure. Its high alumina ceramic insulator optimizes thermal conductivity and dielectric strength, while the multi-rib insulator prevents flash-over for reliable operation. Featuring a mid-projection center electrode and flat seat type, this performance-grade spark plug is built with platinum-tipped electrodes for consistent ignition and lasting reliability. Designed to deliver exceptional value, it is a dependable choice for maintaining peak engine performance.
See More

Autolite – Autolite Copper Resistor Spark Plug: Quick Starts & Smooth Acceleration, 65 (Part No.65)

Autolite Copper Resistor Spark Plug: Quick Starts & Smooth Acceleration, 65

from

$4.49
Autolite Copper spark plugs are expertly crafted to ensure your vehicle delivers reliable performance with every start. Featuring a copper core center electrode, these plugs excel in thermal control and resist fouling, while the high nickel alloy center and ground electrodes provide extended durability. The high alumina multi-rib ceramic insulator enhances thermal conductivity and insulation, offering superior strength under demanding conditions. Designed with a corrosion-resistant nickel-plated shell, these spark plugs are built to last. Their mid-projection center electrode and flat seat type ensure optimal compatibility, while the resistor design minimizes electrical interference. Engineered for quick starts, smooth acceleration, and enhanced fuel economy, these spark plugs are a dependable choice for maintaining your vehicle’s efficiency and performance.
See More

ACDelco – ACDelco Conventional Spark Plug, R44XLS (Part No.R44XLS)

ACDelco Conventional Spark Plug, R44XLS

from

$5.99
ACDelco Gold (Professional) Conventional Spark Plugs are a high quality alternative to Original Equipment (OE) parts. These Conventional Spark Plugs are designed for reliability and efficient performance, and are a high quality replacement for many vehicles on the road today. Their high-quality copper cores and outstanding suppression characteristics deliver reliable performance. They are also available for Marine applications. These premium aftermarket replacement spark plugs are manufactured to meet your expectations for fit, form, and function. ACDelco Gold (Professional) parts are manufactured to meet your expectations for fit, form, and function, making them a smart choice for General Motors vehicles, as well as most makes and models, including special applications. These high-quality parts are backed by General Motors. Some ACDelco Gold parts may have formerly appeared as ACDelco Professional.
See More

E3 – DiamondFire Spark Plug (E3.46): Enhanced Power & Fuel Efficiency (Part No.E3.46)

DiamondFire Spark Plug (E3.46): Enhanced Power & Fuel Efficiency

from

$8.49
The Spark Plugs are the product of years of fundamental research in the combustion field. The unique patented electrode configuration of these new The spark plugs increases the amount of combustion pressure created during each power stroke of an engine, which results in a marked increase in power output, fuel economy, and reduced emissions in all gasoline engines. E3.46 is a 14mm, 0.750 reach plug with a gasket seat. It fits a wide variety of applications from the 60s to early 90s, especially import. E3.46 is widely stocked in automotive retail stores. The automotive plugs have three legs securing the Diamond FIRE electrode to the shell. This allows for excellent heat transfer, and helps to create more turbulence in the cylinder. The patented Diamond FIRE side wire is proven to increase power, reduce fuel consumption and improve hydrocarbon emissions in long-term use.
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Dorman – Help – Dorman – Help Spark Plug Non-Foulers – 14mm Gasket Seat Long Reach, 42004 (Part No.42004)

Dorman - Help Spark Plug Non-Foulers - 14mm Gasket Seat Long Reach, 42004

from

$9.99
This spark plug non fouler is designed for easy installation on specified vehicles to protect spark plugs from fouling and damage. It is engineered for durability and reliable performance.
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Most Popular Spark Plugs for 1966 GMC I2500s

Enhance your 1966 GMC I2500 with one of the 9 Spark Plugs we have in stock, starting at just $4.49.

Autolite – Autolite Copper Resistor Spark Plug: Quick Starts & Smooth Acceleration, 65 (Part No.65)

Autolite Copper Resistor Spark Plug: Quick Starts & Smooth Acceleration, 65

from

$4.49
Autolite Copper spark plugs are expertly crafted to ensure your vehicle delivers reliable performance with every start. Featuring a copper core center electrode, these plugs excel in thermal control and resist fouling, while the high nickel alloy center and ground electrodes provide extended durability. The high alumina multi-rib ceramic insulator enhances thermal conductivity and insulation, offering superior strength under demanding conditions. Designed with a corrosion-resistant nickel-plated shell, these spark plugs are built to last. Their mid-projection center electrode and flat seat type ensure optimal compatibility, while the resistor design minimizes electrical interference. Engineered for quick starts, smooth acceleration, and enhanced fuel economy, these spark plugs are a dependable choice for maintaining your vehicle’s efficiency and performance.
See More

ACDelco – ACDelco Conventional Spark Plug, R44XLS (Part No.R44XLS)

ACDelco Conventional Spark Plug, R44XLS

from

$5.99
ACDelco Gold (Professional) Conventional Spark Plugs are a high quality alternative to Original Equipment (OE) parts. These Conventional Spark Plugs are designed for reliability and efficient performance, and are a high quality replacement for many vehicles on the road today. Their high-quality copper cores and outstanding suppression characteristics deliver reliable performance. They are also available for Marine applications. These premium aftermarket replacement spark plugs are manufactured to meet your expectations for fit, form, and function. ACDelco Gold (Professional) parts are manufactured to meet your expectations for fit, form, and function, making them a smart choice for General Motors vehicles, as well as most makes and models, including special applications. These high-quality parts are backed by General Motors. Some ACDelco Gold parts may have formerly appeared as ACDelco Professional.
See More

Champion – Champion Copper Plus Spark Plug RN14YC – Dependable Performance & Durability, 405 (Part No.405)

Champion Copper Plus Spark Plug RN14YC - Dependable Performance & Durability, 405

from

$5.99
Champion Copper Plus spark plugs deliver dependable ignition performance with proven copper-core technology. The copper core electrode provides excellent conductivity and optimized heat control for consistent sparks while the coated shell protects against corrosion. Champion your engine with spark plugs engineered to improve efficiency and keep your vehicle running at its best.
See More

Autolite – Autolite Platinum Spark Plug: Enhanced Durability & Improved Performance, AP65 (Part No.AP65)

Autolite Platinum Spark Plug: Enhanced Durability & Improved Performance, AP65

from

$5.49
Platinum Spark Plug: Enhanced Durability & Improved Performance is crafted with a platinum center electrode firing tip that ensures quicker firing, smoother starts, and better acceleration while boosting fuel efficiency. Engineered with a platinum firing tip to prevent gap erosion, it offers a longer service life, making it ideal for older engine applications. The high alumina ceramic insulator enhances thermal conductivity and insulation, providing superior strength, while the multi-rib design prevents flash-over for reliable performance. Its nickel-plated shell resists corrosion, ensuring extended durability even in demanding conditions. Featuring a mid-projection standard center electrode design and a flat seat type, this performance-grade spark plug is backed by over 100 years of engineering expertise and a legacy of more than 11 billion plugs sold. Designed in the USA, it combines advanced materials like platinum and nickel to deliver consistent reliability and value for your vehicle.
See More

Champion – Champion Platinum Power Spark Plug RN14PMC – Powerful Performance & Longevity, 3405 (Part No.3405)

Champion Platinum Power Spark Plug RN14PMC - Powerful Performance & Longevity, 3405

from

$5.99
Champion Platinum Power spark plugs deliver powerful performance with the exclusive Premium alloy that reaches and sustains the correct operating temperature. A fine-wire center electrode and V-trimmed ground electrode provides sharp spark focus and reliable ignition for consistent combustion under demanding conditions. Champion your engine with spark plugs engineered to improve efficiency and keep your vehicle running at its best.
See More

E3 – DiamondFire Spark Plug (E3.46): Enhanced Power & Fuel Efficiency (Part No.E3.46)

DiamondFire Spark Plug (E3.46): Enhanced Power & Fuel Efficiency

from

$8.49
The Spark Plugs are the product of years of fundamental research in the combustion field. The unique patented electrode configuration of these new The spark plugs increases the amount of combustion pressure created during each power stroke of an engine, which results in a marked increase in power output, fuel economy, and reduced emissions in all gasoline engines. E3.46 is a 14mm, 0.750 reach plug with a gasket seat. It fits a wide variety of applications from the 60s to early 90s, especially import. E3.46 is widely stocked in automotive retail stores. The automotive plugs have three legs securing the Diamond FIRE electrode to the shell. This allows for excellent heat transfer, and helps to create more turbulence in the cylinder. The patented Diamond FIRE side wire is proven to increase power, reduce fuel consumption and improve hydrocarbon emissions in long-term use.
See More

ACDelco – ACDelco RAPIDFIRE Spark Plug, 4 (Part No.4)

ACDelco RAPIDFIRE Spark Plug, 4

from

$7.99
ACDelco Gold (Professional) RAPIDFIRE Spark Plugs are a high quality alternative to Original Equipment (OE) parts. These RAPIDFIRE Single Platinum Performance Spark Plugs are designed for everyday use and are a high quality replacement for many vehicles on the road today. These premium aftermarket spark plugs have high-quality suppressors that help prevent misfiring, an improved plug to boot seal, and a pure copper core for greater durability. These premium aftermarket replacement spark plugs are manufactured to meet your expectations for fit, form, and function. ACDelco Gold (Professional) parts are manufactured to meet your expectations for fit, form, and function, making them a smart choice for General Motors vehicles, as well as most makes and models, including special applications. These high-quality parts are backed by General Motors. Some ACDelco Gold parts may have formerly appeared as ACDelco Professional.
See More

Autolite – Autolite Double Platinum Spark Plug: Enhanced Durability & Performance, APP65 (Part No.APP65)

Autolite Double Platinum Spark Plug: Enhanced Durability & Performance, APP65

from

$7.49
Double Platinum Spark Plug offers enhanced durability and performance with its platinum-to-platinum design, effectively reducing gap erosion and minimizing misfires for a longer service life. Engineered for distributor-less ignition system (DIS) engines, it outperforms copper and standard platinum plugs. The yttrium-enhanced ground electrode ensures superior heat transfer, maintaining durability under high temperatures and pressure. Its high alumina ceramic insulator optimizes thermal conductivity and dielectric strength, while the multi-rib insulator prevents flash-over for reliable operation. Featuring a mid-projection center electrode and flat seat type, this performance-grade spark plug is built with platinum-tipped electrodes for consistent ignition and lasting reliability. Designed to deliver exceptional value, it is a dependable choice for maintaining peak engine performance.
See More

Motorcraft – Motorcraft Spark Plug: Reliable Ignition for Optimal Engine Performance, SP-416-X (Part No.SP-416-X)

Motorcraft Spark Plug: Reliable Ignition for Optimal Engine Performance, SP-416-X

from

$7.29
Ensure your engine runs smoothly and efficiently with this high-quality spark plug, designed to deliver reliable ignition and optimal performance. Engineered for durability and precision, it provides consistent spark energy to maximize fuel combustion, improving both power output and fuel efficiency. Built to withstand extreme temperatures and pressures, this spark plug ensures long-lasting performance, reducing the need for frequent replacements. Its compatibility with a wide range of vehicles makes it a versatile choice for maintaining peak engine functionality. Whether you’re looking to restore lost performance or maintain your vehicle’s reliability, this spark plug offers exceptional value and dependable operation.
See More

Top-Rated Spark Plug Brands For Your 1966 GMC I2500

When it comes to finding the perfect Spark Plug for your 1966 GMC I2500, Advance Auto Parts has you covered with a wide selection of high-quality OEM and aftermarket options from 5 trusted brands. We carry the most popular Spark Plug brands including Champion, ACDelco, and Autolite, and more, all known for their exceptional customer ratings (average brand rating of 4.8 stars) and competitive prices, as low as $4.49. Purchasing a Spark Plug from us here at Advance Auto Parts is a smart move for both you and your 1966 GMC I2500, providing peace of mind with parts that meet or exceed OEM standards.

Popular Champion 1966 GMC I2500 Spark Plugs

If you’re looking for a top-quality Spark Plug for your 1966 GMC I2500, Advance Auto Parts has exactly what you need with our selection of Champion Spark Plugs. We have 2 Champion Spark Plugs in stock for this fitment, all known for their durability and precision fit. With prices starting at just $5.99, you’ll find the perfect Spark Plug for your needs and budget. Champion Spark Plugs for the 1966 GMC I2500 come highly rated, with over 4 customer reviews and an impressive average rating of 4.8 stars. Choosing a Champion Spark Plug from Advance Auto Parts is a smart move to ensure quality and value for your vehicle.

Top-Quality ACDelco 1966 GMC I2500 Spark Plugs

For those in search of a high-quality Spark Plug for their 1966 GMC I2500, Advance Auto Parts offers a great selection of ACDelco Spark Plugs. With 1 ACDelco Spark Plugs in stock, you can trust you’re getting top-tier parts designed for durability and a perfect fit. Prices for these Spark Plugs start at just $5.99, giving you a range of options to suit your budget. Backed by over 6 customer ratings and an average rating of 4.7 stars, ACDelco Spark Plugs provide both reliability and excellent performance. Choosing a ACDelco Spark Plug from Advance Auto Parts is a smart investment in your vehicle’s performance and longevity.
ACDelco Conventional Spark Plug, R44XLS
from $5.99
(6)
ACDelco Conventional Spark Plug, R44XLS
“Review is not so much about spark plugs, rather Advance Auto Parts, the the great job they do from beginning to end of sale.”

FAQs for 1966 GMC I2500 Spark Plugs

What are the best-selling Spark Plugs for 1966 GMC I2500s?

Out of 9 Spark Plugs that fit 1966 GMC I2500s, the following parts are the top sellers:

What’s the price range for 1966 GMC I2500 Spark Plugs?

The prices of Spark Plugs for the 1966 GMC I2500 range from $4.49 up to $8.49 for the most premium parts.

What is the average price of a Spark Plug for a 1966 GMC I2500?

The average price for Spark Plugs for the 1966 GMC I2500 is $6.41. Keep in mind the variety of part types within our Spark Plug category, where you are likely to find a wide range of prices across a variety of parts and components.

Does Advance Auto Parts sell Spark Plugs for any other 1966 GMC models?

Yes. We stock Spark Plugs for 19 other popular 1966 GMC models. Some of the most popular are 1966 K15/K1500 Pickup Spark Plugs, 1966 Suburban Spark Plugs, 1966 G1000 Series Spark Plugs, 1966 PB1000 Series Spark Plugs, and 1966 I1500 Spark Plugs.

What are the top-rated Spark Plugs that fit the 1966 GMC I2500?

The one 1966 GMC I2500 Spark Plug we have in stock is the Autolite Copper Resistor Spark Plug: Quick Starts & Smooth Acceleration, 65. It is rated 5 stars and costs $4.49.

What types of Spark Plugs do you sell for my 1966 GMC I2500?

We currently have just 1 Spark Plug in stock for a 1966 GMC I2500, and as of 8/2/26, it is a Spark Plug.

Can I get help with 1966 GMC I2500 Spark Plug orders?

Contact our customer support team by chat or phone, through the help desk page, where you can find instant answers about GMC Spark Plugs and more.

What is your return policy for GMC I2500 Spark Plugs?

Advance Auto Parts keeps returns simple. For new GMC I2500 Spark Plugs and accessories, your online orders can be returned, in their original condition, within 45 days. For requirements, see the returns page.