Workhorse W42 Spark Plugs

Your Workhorse W42 will be happy to know that the search for the right Spark Plugs you’ve been looking for is over! Advance Auto Parts has 8 different Spark Plugs for your vehicle, ready for shipping or in-store pick up. The best part is, our Workhorse W42 Spark Plugs start from as little as $2.99.

When it comes to your Workhorse W42, you want parts and products from only trusted brands. Here at Advance Auto Parts, we work with only top reliable Spark Plugs brands so you can shop with complete confidence. Some of our top Spark Plugs brands are ACDelco and Champion. We’re sure you will get the right product to keep that W42 running for a long time.

We even have reviews of our OEM and aftermarket Spark Plugs products to help you buy with confidence. Hear from other customers via the 638 reviews on parts for your Workhorse W42.

Shop online, find the best price on the right product, and have it shipped right to your door. If you prefer to shop in person for the right Spark Plugs for your W42, visit one of our local Advance Auto Parts locations and you’ll be back on the road in no time!

Compare 25 Workhorse Spark Plugs

ACDelco – Double Platinum Spark Plug: Original Equipment Replacement (Part No.41-962)

Double Platinum Spark Plug: Original Equipment Replacement

from

$9.79
ACDelco GM Original Equipment Double Platinum Spark Plugs are designed, engineered, and tested to rigorous standards, and are backed by General Motors. With a copper core and double platinum pads on the center electrode, these plugs are designed to deliver long-lasting performance. ACDelco GM Original Equipment parts are the true OE parts installed during the production or validated by General Motors for GM vehicles. Some ACDelco GM Original Equipment parts may have formerly appeared as GM Genuine Parts (OE) or ACDelco Professional.

Product Features:
  • One-piece, fired-in suppressor seal blends three glass types for a gas-tight seal that helps reduce radio frequency and engine interference, regulate spark plug energy, and protect against compression pressures for long life
  • Double platinum point pad on center and ground electrode offer excellent durability and consistent voltage demands to help reduce wear on ignition system
  • Approved by US Legal 7/31/19
  • Some ACDelco GM Original Equipment parts may have formerly appeared as GM Genuine Parts (OE) or ACDelco Professional
  • ACDelco GM Original Equipment parts are designed, engineered and tested to rigorous standards, and are backed by General Motors
  • GM Engineers design and validate OE parts specifically for your Chevrolet, Buick, GMC, or Cadillac vehicle
  • GM regularly updates production and service part designs to integrate new materials and technologies
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Motorcraft – Double Platinum Spark Plug: Enhances Durability & Reduces Misfires (Part No.SP-486)

Double Platinum Spark Plug: Enhances Durability & Reduces Misfires

from

$7.29
Motorcraft Spark Plugs are original equipment on Ford Motor Company vehicles, engineered to meet strict Ford engineering standards for performance and reliability. These spark plugs are matched to specific engines to provide enhanced durability, eliminate misfires, reduce fuel consumption, and optimize emissions. With a platinum center and ground electrode tip, they are resistant to oxidation and arc erosion, ensuring long-lasting performance. The multi-rib insulator protects against misfire, and they are backed by Motorcraft’s Service Parts Warranty. Designed for exact fit in Ford, Lincoln, and Mercury vehicles, they also help prevent false check engine lights. With service intervals of up to 100,000 miles, Motorcraft Spark Plugs are crafted from high-quality materials to deliver reliable performance for almost any application, making them the same components that were in the vehicle when it was manufactured.

Product Features:
  • Motorcraft spark plugs are matched to specific engines to provide enhanced durability, eliminate misfires, reduce fuel consumption and optimize emissions.
  • Backed by Motorcraft’s Service Parts Warranty
  • Exact fit for Ford, Lincoln and Mercury vehicles
  • Resistant to oxidation and arc erosion.
  • Multi-rib insulator protects against misfire.
  • Service intervals of up to 100,000 miles.
  • Motorcraft Spark Plugs are designed with high quality materials to provide reliable performance for almost any application.
  • Motorcraft Spark Plugs are what was in the vehicle when it was manufactured
  • Motorcraft ignition components help prevent false check engine lights.
  • Enhanced Durability: Engineered with a platinum center and ground electrode tip, these spark plugs are resistant to oxidation and arc erosion, ensuring long-lasting performance.
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ACDelco – Double Platinum Spark Plug: Original Equipment Replacement (Part No.41-979)

Double Platinum Spark Plug: Original Equipment Replacement

from

$9.79
ACDelco GM Original Equipment Double Platinum Spark Plugs are designed, engineered, and tested to rigorous standards, and are backed by General Motors. With a copper core and double platinum pads on the center electrode, these plugs are designed to deliver long-lasting performance. ACDelco GM Original Equipment parts are the true OE parts installed during the production or validated by General Motors for GM vehicles. Some ACDelco GM Original Equipment parts may have formerly appeared as GM Genuine Parts (OE) or ACDelco Professional.

Product Features:
  • One-piece, fired-in suppressor seal blends three glass types for a gas-tight seal that helps reduce radio frequency and engine interference, regulate spark plug energy, and protect against compression pressures for long life
  • Double platinum point pad on center and ground electrode offer excellent durability and consistent voltage demands to help reduce wear on ignition system
  • Some ACDelco GM Original Equipment parts may have formerly appeared as GM Genuine Parts (OE) or ACDelco Professional
  • ACDelco GM Original Equipment parts are designed, engineered and tested to rigorous standards, and are backed by General Motors
  • GM Engineers design and validate OE parts specifically for your Chevrolet, Buick, GMC, or Cadillac vehicle
  • GM regularly updates production and service part designs to integrate new materials and technologies
  • Copper Core: Designed with a copper core to provide excellent heat transfer and electrical conductivity.
  • Conical Seat Type: Equipped with a conical seat type for a secure fit and optimal performance.
  • Built-in Resistor: Includes a built-in resistor to reduce radio frequency interference and ensure reliable operation.
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NGK – OE Series Laser Iridium Spark Plug: Fine Wire Tip Design, IZTR5B11 (Part No.1465)

OE Series Laser Iridium Spark Plug: Fine Wire Tip Design, IZTR5B11

from

$15.79
NGK Laser Iridium spark plugs offer the best combination of performance and longevity. Engineered specifically for OE applications, Laser Iridium spark plugs are tested to the highest standards to ensure quality and durability. Iridium tipped center electrode provides durability six times harder than platinum. NGKs high grade pure alumina ceramic and 98 percent pure copper core prevents the spark plug from overheating while providing reliable starts. Most Laser Iridium spark plugs feature a platinum pad on the ground electrode for even wear in distributorless ignition systems.

Product Features:
  • ACTUAL OE or EQUIVALENT DESIGN: OEM quality construction fine wire iridium alloy center electrode provides consistent performance
  • IRIDIUM ALLOY CENTER ELECTRODE: Iridium’s density (6x that of platinum) and extremely high melting point is perfect for modern high efficiency engines
  • PLATINUM TIP GROUND ELECTRODE: Unless OE specified, platinum protection at the ground electrode provides excellent ignitability and service life
  • SOLID COPPER CORE: 98% pure copper core offers superior heat dissipation, conductivity and ultra wide heat ranges
  • TRIVALENT METAL PLATING: Delivers superior anti-corrosion and anti-seizing properties, ensuring ease of installation and removal
  • RECOMMENDED USAGE: Best for vehicles with OE fine wire iridium alloy plugs
  • Superior Durability: The iridium-tipped center electrode is six times harder than platinum, ensuring long-lasting performance and reliability.
  • OE Application Specific: Engineered specifically for Original Equipment (OE) applications, ensuring a perfect fit and optimal performance.
  • Fine Wire Tip Design: The fine wire tip design of the IZTR5B11 model enhances ignition efficiency and performance.
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Champion – Iridium Spark Plug: Maximum Performance, OE Replacement, RS14WYPB5 (Part No.9404)

Iridium Spark Plug: Maximum Performance, OE Replacement, RS14WYPB5

from

$8.49
Champion® Iridium – the ultimate element. This spark plug’s fine-wire iridium center and platinum ground electrodes provide the sharpest spark focus for maximum performance.

Product Features:
  • Champion Iridium – Maximum Performance. Premium Spark Plug
  • Iridium center electrode delivers maximum life
  • Fine-wire center electrode and V-trimmed for greater ignitability
  • V-trimmed ground electrode promotes sharper spark focus
  • Maintains stable operating temperature under all engine loads
  • Heat-Active┐ alloy allows electrodes to reach optimal temperature quickly
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NGK – OE Series V-Power Nickel Spark Plug: V-Groove Tip Design, TR5 (Part No.2238)

OE Series V-Power Nickel Spark Plug: V-Groove Tip Design, TR5

from

$4.49
NGK V-Power spark plugs offer reliable performance and improved ignitability over standard nickel plugs. Engineered specifically for OE applications, the special V-cut nickel alloy center electrode and concave ground electrode of NGK’s V-Power spark plug increases ignitability providing quicker starts and smoother idle. NGK’s legendary high grade alumina silicate ceramic creates a stronger insulator for optimal dielectric performance. Trivalent metal plating ensures superior anti-corrosion and anti-seizing properties.

Product Features:
  • ACTUAL OE or EQUIVALENT DESIGN: OEM quality construction nickel alloy center electrode with V-groove provides consistent performance
  • RECOMMENDED USAGE: Best for vehicles with OE nickel alloy plugs, not recommended on vehicles with factory precious metal plugs
  • NGK’s OE CERAMIC TECHNOLOGY: High grade alumina silicate ceramic creates a stronger insulator for optimal dielectric performance
  • SOLID COPPER CORE: 98% pure copper core offers superior heat dissipation, conductivity and ultra wide heat ranges
  • COLD-ROLLED THREADS: Prevents cross-threading and damage to cylinder heads
  • TRIVALENT METAL PLATING: Delivers superior anti-corrosion and anti-seizing properties, ensuring ease of installation and removal
  • Enhanced Ignitability: The V-cut nickel alloy center electrode and concave ground electrode design of NGK V-Power spark plugs provide quicker starts and smoother idle.
  • OE Application Specific: Engineered specifically for Original Equipment (OE) applications, ensuring compatibility and reliable performance.
  • V-Groove Tip Design: The unique V-groove tip design of the center electrode enhances ignitability and overall engine performance.
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NGK – G-Power Spark Plug: Single Platinum Tip Design, TR5GP (Part No.3186)

G-Power Spark Plug: Single Platinum Tip Design, TR5GP

from

$6.29
NGK G-Power Platinum spark plugs are the best single platinum spark plugs at an economical price. G-Power plugs feature a fine wire platinum center electrode and a trapezoidal cut ground electrode that offers increased durability, improved fuel efficiency, lower emissions, faster starts and quicker acceleration over conventional nickel spark plugs. An excellent upgrade for vehicles which used nickel alloy spark plugs originally. For better performance consider upgrading to a NGK Iridium IX plug. For even greater performance consider upgrading to a NGK RUTHENIUM HX plug.

Product Features:
  • SINGLE PLATINUM TIP: Fine wire 0.6 millimeter platinum tip center electrode ensures improved durability and a consistently stable spark
  • PLATINUM ALLOY: G-Power platinum provides exceptional value with increased performance and longer service intervals than factory nickel plugs
  • TRAPEZOIDAL CUT GROUND ELECTRODE: Reduces quenching design produces improved ignitability and performance
  • SOLID COPPER CORE: 98% pure copper core offers superior heat dissipation, conductivity and ultra wide heat ranges
  • COLD-ROLLED THREADS: Prevents cross-threading and damage to cylinder heads
  • RECOMMENDED USAGE: Lower cost alternative to double precious metal spark plugs or as an upgrade to OE nickel alloy spark plugs
  • Tapered Seat Type: The tapered seat type ensures a secure fit and optimal performance in compatible vehicles.
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ACDelco – Copper Core Spark Plug: Original Equipment Replacement (Part No.R44LTS6)

Copper Core Spark Plug: Original Equipment Replacement

from

$4.99
ACDelco GM Original Equipment Conventional Spark Plugs are designed, engineered, and tested to rigorous standards, and are backed by General Motors. 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 GM Original Equipment parts are the true OE parts installed during the production of or validated by General Motors for GM vehicles. Some ACDelco GM Original Equipment parts may have formerly appeared as GM Genuine Parts (OE) or ACDelco Professional.

Product Features:
  • Black Onyx coating helps reduce corrosion
  • Copper core provides great heat transfer and helps maximize plug durability
  • Ribbed suppressor seal extends resistance and helps prevent spark ‘flash over’ and misfires
  • Nickel-chrome alloy sheathing helps prevent corrosion on center electrode
  • Available for use in Marine applications
  • Some ACDelco GM Original Equipment parts may have formerly appeared as GM Genuine Parts (OE) or ACDelco Professional
  • ACDelco GM Original Equipment parts are designed, engineered and tested to rigorous standards, and are backed by General Motors
  • GM Engineers design and validate OE parts specifically for your Chevrolet, Buick, GMC, or Cadillac vehicle
  • GM regularly updates production and service part designs to integrate new materials and technologies
  • High-Quality Copper Core: Designed with high-quality copper cores for reliable and efficient performance.
  • Nickel Center Electrode Tip: Features a nickel center electrode tip for enhanced durability and performance.
  • Outstanding Suppression Characteristics: Delivers reliable performance with excellent suppression characteristics.
  • OE Replacement: True Original Equipment parts installed during GM vehicle production, ensuring perfect fit, form, and function.
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ACDelco – Copper Core Spark Plug: Original Equipment Replacement (Part No.R44LTSM)

Copper Core Spark Plug: Original Equipment Replacement

from

$4.99
ACDelco GM Original Equipment Conventional Spark Plugs are designed, engineered, and tested to rigorous standards, and are backed by General Motors. 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 GM Original Equipment parts are the true OE parts installed during the production of or validated by General Motors for GM vehicles. Some ACDelco GM Original Equipment parts may have formerly appeared as GM Genuine Parts (OE) or ACDelco Professional.

Product Features:
  • GM regularly updates production and service part designs to integrate new materials and technologies
  • High-Quality Copper Core: Designed with high-quality copper cores for reliable performance and efficient operation.
  • Nickel Center Electrode Tip: Features a nickel center electrode tip for enhanced durability and consistent performance.
  • Outstanding Suppression Characteristics: Engineered to deliver outstanding suppression characteristics, ensuring smooth engine operation.
  • OE Fit, Form, and Function: Manufactured to meet original equipment specifications for fit, form, and function, ensuring a perfect replacement for GM vehicles.
  • Versatile Applications: Providing a high-quality replacement for a wide range of vehicles.
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Autolite – Platinum Spark Plug: Fires Cleaner, Easier Starts, Quicker Acceleration (Part No.AP5245)

Platinum Spark Plug: Fires Cleaner, Easier Starts, Quicker Acceleration

from

$4.79
Autolite has over 100 years of engineering experience and has sold over 11 billion plugs. Designed and engineered in the USA, Autolite Platinum spark plugs provide a center wire platinum firing tip which provides reduced gap erosion, fewer misfires, better performance and increased durability. Consider upgrading to Autolite Double Platinum or Iridium XP spark plugs for increased performance.

Product Features:
  • High nickel alloy side electrode maintains precise gap
  • Full platinum tip assures virtually no gap erosion for long life
  • Necked-down center electrode fires quicker, cleaner with less voltage for easier starts, quicker acceleration and improved fuel economy (as compared to standard plugs)
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Autolite – Platinum Spark Plug: Fires Cleaner, Easier Starts, Quicker Acceleration (Part No.AP605)

Platinum Spark Plug: Fires Cleaner, Easier Starts, Quicker Acceleration

from

$4.49
Autolite has over 100 years of engineering experience and has sold over 11 billion plugs. Designed and engineered in the USA, Autolite Platinum spark plugs provide a center wire platinum firing tip which provides reduced gap erosion, fewer misfires, better performance and increased durability. Consider upgrading to Autolite Double Platinum or Iridium XP spark plugs for increased performance.

Product Features:
  • High nickel alloy side electrode maintains precise gap
  • Full platinum tip assures virtually no gap erosion for long life
  • Necked-down center electrode fires quicker, cleaner with less voltage for easier starts, quicker acceleration and improved fuel economy (as compared to standard plugs)
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Autolite – Double Platinum Spark Plug: Platinum Firing, Superior Durability, Longer Life (Part No.APP5245)

Double Platinum Spark Plug: Platinum Firing, Superior Durability, Longer Life

from

$6.79
With over 100 years of engineering expertise and more than 11 billion plugs sold, Autolite delivers exceptional quality. Designed and engineered in the USA, these spark plugs feature platinum-to-platinum firing, virtually eliminating gap erosion and reducing misfires. The OE design and full-platinum tips on both the center and side electrodes optimize engine performance for a longer life and improved fuel economy. The platinum ball welding process ensures a consistent point of contact for enhanced adhesion, while the tapered seat type further contributes to the plug’s superior durability.

Product Features:
  • Works to optimize engine performance for a longer life and improved fuel economy
  • OE design
  • Full-platinum tips; platinum on both the center and side electrodes to promote reduced gap wear
  • Platinum ball welding process provides a consistent point of contact for enhanced adhesion
  • Engineered in the USA: Developed with over 100 years of engineering expertise, ensuring high-quality and reliable performance.
  • Exceptional Quality: With more than 11 billion plugs sold, Autolite delivers trusted and proven quality in every spark plug.
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NGK – Iridium IX Spark Plug: Single Iridium Fine Wire, TR5IX (Part No.7397)

Iridium IX Spark Plug: Single Iridium Fine Wire, TR5IX

from

$11.99
NGK Iridium IX spark plugs are specifically designed for the performance enthusiast. Iridium IX provides outstanding acceleration, high fuel efficiency and durability. NGK Iridium IX plugs offer extreme ignitability and exceptional anti-fouling. Tapered cut ground electrode provides improved starting, idling and throttle response. The Iridium fine wire center electrode’s durability is six times harder than platinum. Iridium alloy’s extremely high melting point is perfect for today’s engines. For even greater performance consider upgrading to an NGK Ruthenium HX plug.

Product Features:
  • SINGLE IRIDIUM TIP: Fine wire 0.6 millimeter iridium tip center electrode ensures high durability and a consistently stable spark
  • IRIDIUM ALLOY CENTER ELECTRODE: Iridium’s density (6x that of platinum) and extremely high melting point is perfect for modern high efficiency engines
  • TAPERED CUT GROUND ELECTRODE: Reduced quenching design produces outstanding ignitability, improved acceleration, fuel efficiency and durability
  • SOLID COPPER CORE: 98% pure copper core offers superior heat dissipation, conductivity and ultra wide heat ranges
  • TRIVALENT METAL PLATING: Delivers superior anti-corrosion and anti-seizing properties, ensuring ease of installation and removal
  • RECOMMENDED USAGE: Modified or high performance applications, or as an upgrade to OE nickel alloy spark plugs
  • Outstanding Acceleration and High Fuel Efficiency: NGK Iridium IX spark plugs are engineered to deliver exceptional acceleration and improved fuel efficiency, making them ideal for performance enthusiasts.
  • Extreme Ignitability and Anti-Fouling: These spark plugs offer extreme ignitability and exceptional resistance to fouling, ensuring reliable performance in various driving conditions.
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Autolite – Copper Spark Plug: Delivers Quick Starts, Good Fuel Economy, Smooth Acceleration (Part No.605)

Copper Spark Plug: Delivers Quick Starts, Good Fuel Economy, Smooth Acceleration

from

$3.49
With over 100 years of engineering expertise and more than 11 billion plugs sold, Autolite continues to set the standard in spark plug technology. Designed and engineered in the USA, these spark plugs feature a copper cored center electrode for higher thermal conductivity, ensuring quick starts and smooth acceleration. The specially engineered high nickel alloy center and ground electrode provide extended life, while the high alumina ceramic offers high dielectric strength. Additionally, the leak-proof, heat-fused internal seal enhances durability, and the multi-rib insulator prevents flash-over. The tapered seat type ensures a perfect fit, making these spark plugs a reliable choice for your vehicle.

Product Features:
  • Copper cored center electrode for higher thermal conductivity
  • Specially engineered high nickel alloy center and ground electrode for extended life
  • High alumina ceramic for high dielectric strength
  • Leak proof, heat fused internal seal for durability
  • Multi-rib insulator prevents flash-over
  • Perfect Fit: The tapered seat type ensures a perfect fit, making installation easy and reliable for your vehicle.
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Autolite – Copper Spark Plug: Delivers Quick Starts, Good Fuel Economy, Smooth Acceleration (Part No.5245)

Copper Spark Plug: Delivers Quick Starts, Good Fuel Economy, Smooth Acceleration

from

$3.49
With over 100 years of engineering expertise and over 11 billion plugs sold, Autolite continues to set the standard in spark plug technology. Designed and engineered in the USA, these spark plugs feature a copper cored center electrode for higher thermal conductivity, a specially engineered high nickel alloy center and ground electrode for extended life, and high alumina ceramic for high dielectric strength. Additionally, the leak-proof, heat-fused internal seal ensures durability, while the multi-rib insulator prevents flash-over, making these plugs a reliable choice for enhancing your vehicle’s performance.

Product Features:
  • Copper cored center electrode for higher thermal conductivity
  • Specially engineered high nickel alloy center and ground electrode for extended life
  • High alumina ceramic for high dielectric strength
  • Leak proof, heat fused internal seal for durability
  • Multi-rib insulator prevents flash-over
  • Quick Starts: The Autolite Copper Spark Plug ensures quick engine starts, enhancing your vehicle’s reliability and performance.
  • Good Fuel Economy: Designed to optimize fuel efficiency, these spark plugs help you save on fuel costs while maintaining excellent engine performance.
  • Smooth Acceleration: Experience smoother acceleration with the high-quality engineering of Autolite Copper Spark Plugs, providing a more responsive driving experience.
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Champion – Copper Plus Spark Plug: Dependable Performance, OE Replacement, RS12YC (Part No.401)

Copper Plus Spark Plug: Dependable Performance, OE Replacement, RS12YC

from

$2.99
Dependable Performance, OE Replacement, RS12YC. This Champion® spark plug features a copper core electrode that provides increased conductivity and heat control for good overall wear. The Copper Plus design ensures dependable performance and durability, while the copper core center electrode allows for accurate control of heat range, extending the spark plug’s life. Built to ISO and SAE standards, it offers superior corrosion resistance and proven performance. The nickel center electrode tip and tapered seat type further enhance its reliability, making it an excellent choice for maintaining your engine’s efficiency.

Product Features:
  • Copper Plus – Dependable Performance and Durability
  • Copper core center electrode allows for accurate control of heat range for longer life
  • Superior corrosion resistance
  • Built to ISO and SAE standards for proven performance
  • Built to ISO and SAE standards for proven performance
  • Enhanced Conductivity and Heat Control: The Champion Copper Plus Spark Plug features a copper core electrode that provides increased conductivity and heat control, ensuring good overall wear and extending the spark plug’s life.
  • Reliable Nickel Center Electrode Tip: Featuring a nickel center electrode tip and a tapered seat type, this spark plug enhances reliability and ensures optimal engine performance.
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ACDelco – RAPIDFIRE Premium Platinum Tip Copper Core Spark Plug: Reduces Misfires & Enhances Durability (Part No.14)

RAPIDFIRE Premium Platinum Tip Copper Core Spark Plug: Reduces Misfires & Enhances Durability

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.

Product Features:
  • Solid state suppressor, with two-piece glass and brass seal, can help reduce radio frequency interference, regulates spark energy for long electrode life, and helps protect against high combustion pressures
  • Pure copper core provides great heat transfer and helps maximize plug durability
  • Platinum on center electrode enables superior spark characteristics and can reduce voltage requirements of the ignition system
  • Ribless insulator helps optimize plug to boot seal
  • Some ACDelco Gold parts may have formerly appeared as ACDelco Professional
  • Premium aftermarket replacement part
  • Manufactured to meet specifications for fit, form, and function for General Motors vehicles as well as most makes and models
  • High-Quality Suppressors: ACDelco Gold RAPIDFIRE Spark Plugs feature high-quality suppressors that help prevent misfiring, ensuring reliable performance for everyday use.
  • Improved Plug to Boot Seal: Designed with an improved plug to boot seal, these spark plugs provide a secure fit, enhancing overall engine performance and longevity.
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Autolite – Double Platinum Spark Plug: Platinum Firing, Superior Durability, Longer Life (Part No.APP605)

Double Platinum Spark Plug: Platinum Firing, Superior Durability, Longer Life

from

$6.79
With over 100 years of engineering expertise and more than 11 billion plugs sold, Autolite delivers exceptional quality. Designed and engineered in the USA, these spark plugs feature platinum-to-platinum firing, virtually eliminating gap erosion and reducing misfires. The OE design and full-platinum tips on both the center and side electrodes optimize engine performance for a longer life and improved fuel economy. The platinum ball welding process ensures a consistent point of contact for enhanced adhesion, while the tapered seat type further enhances durability. Consider upgrading to Autolite Iridium XP spark plugs for increased performance.

Product Features:
  • Works to optimize engine performance for a longer life and improved fuel economy
  • OE design
  • Full-platinum tips; platinum on both the center and side electrodes to promote reduced gap wear
  • Platinum ball welding process provides a consistent point of contact for enhanced adhesion
  • Engineered in the USA: Developed with over 100 years of engineering expertise, ensuring exceptional quality and reliability.
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Champion – Copper Plus Spark Plug: Dependable Performance, OE Replacement, RS14YC6 (Part No.13)

Copper Plus Spark Plug: Dependable Performance, OE Replacement, RS14YC6

from

$2.99
This Champion® spark plug features a copper core electrode that provides increased conductivity and heat control for good overall wear. The Copper Plus design ensures dependable performance and durability, while the copper core center electrode allows for accurate control of heat range, extending the spark plug’s life. Built to ISO and SAE standards, it offers superior corrosion resistance and proven performance. The nickel center electrode tip and tapered seat type further enhance its reliability, making it a top choice for maintaining your engine’s efficiency.

Product Features:
  • Copper Plus – Dependable Performance and Durability
  • Copper core center electrode allows for accurate control of heat range for longer life
  • Superior corrosion resistance
  • Built to ISO and SAE standards for proven performance
  • Built to ISO and SAE standards for proven performance
  • Nickel Center Electrode Tip: Equipped with a nickel center electrode tip, this spark plug offers superior durability and reliable performance, making it a dependable choice for maintaining engine efficiency.
  • Tapered Seat Type: The tapered seat type design of the Champion Copper Plus Spark Plug ensures a secure fit and optimal performance, contributing to the overall reliability of your engine.
  • OE Replacement: Designed as an OE replacement, the Champion Copper Plus Spark Plug guarantees dependable performance and durability, making it an ideal choice for maintaining your vehicle’s engine.
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ACDelco – Double Platinum Spark Plug: Original Equipment Replacement (Part No.41-942)

Double Platinum Spark Plug: Original Equipment Replacement

from

$9.79
ACDelco Professional Double Platinum Spark Plugs are premium aftermarket plugs, and are a high quality replacement for many vehicles on the road today. With a copper core and double platinum pads on the center electrode, these plugs are designed to deliver long-lasting performance. These premium aftermarket replacement spark plugs are manufactured to meet your expectations for fit, form, and function.

Product Features:
  • One-piece, fired-in suppressor seal blends three glass types for a gas-tight seal that helps reduce radio frequency and engine interference, regulate spark plug energy, and protect against compression pressures for long life
  • Double platinum point pad on center and ground electrode offer excellent durability and consistent voltage demands to help reduce wear on ignition system
  • Pure copper core results in cooler electrode temperature for maximized durability and fouling resistance
  • Some ACDelco GM Original Equipment parts may have formerly appeared as GM Genuine Parts (OE) or ACDelco Professional
  • ACDelco GM Original Equipment parts are designed, engineered and tested to rigorous standards, and are backed by General Motors
  • GM Engineers design and validate OE parts specifically for your Chevrolet, Buick, GMC, or Cadillac vehicle
  • GM regularly updates production and service part designs to integrate new materials and technologies
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Champion – Platinum Power Spark Plug: Powerful Perfromance, OE Replacement, RS14PYC6 (Part No.3013)

Platinum Power Spark Plug: Powerful Perfromance, OE Replacement, RS14PYC6

from

$4.49
Champion® Platinum Power spark plugs deliver powerful performance with their premium design. Featuring a platinum center electrode for long life and a fine-wire center electrode for greater ignitability, these spark plugs ensure optimal engine performance. The V-trimmed ground electrode promotes sharper spark focus, while the exclusive Heat-Active alloy allows electrodes to reach optimal temperature. The platinum-tipped center wire resists wear and helps maintain the proper gap specification over the life of the plug, making it a reliable choice for your vehicle.

Product Features:
  • Platinum Power- Premium Spark Plug. Powerful Performance.
  • Platinum center electrode for long life
  • Fine-wire center electrode for greater ignitability
  • V-trimmed ground electrode promotes sharper spark focus
  • Heat-Active alloy allows electrodes to reach optimal temperature
  • Platinum tipped center wire resists wear and helps to maintain proper gap spec over life of the plug
  • Platinum Center Electrode: Features a platinum center electrode for extended durability and long life.
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Champion – Double Platinum & Power Spark Plug Exceptional Perf OE Replacement RS14PYPB5 (Part No.7940)

Double Platinum & Power Spark Plug Exceptional Perf OE Replacement RS14PYPB5

from

$6.29
Champion® Double Platinum Power spark plugs deliver more powerful performance with their premium design. Featuring a platinum center and ground electrode, these spark plugs offer greater wear resistance and maintain a stable operating temperature under all engine loads. The fine-wire center electrode ensures greater ignitability, while the V-trimmed ground electrode promotes sharper spark focus. The exclusive Heat-Active alloy allows the electrodes to reach optimal temperature, ensuring maximum life and performance.

Product Features:
  • Double Platinum Power – Premium Spark Plug. More Powerful Performance.
  • Platinum center and ground electrode for greater wear resistance
  • Maintains stable operating temperature under all engine loads
  • Fine-wire center electrode for greater ignitability
  • V-trimmed ground electrode promotes sharper spark focus
  • Heat-Active alloy allows electrodes to reach optimal temperature
  • OE Replacement: Designed as an original equipment replacement, ensuring compatibility and reliable performance for your vehicle.
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ACDelco – Rapidfire Spark Plug (Part No.6)

Rapidfire Spark Plug

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.

Product Features:
  • Solid state suppressor, with two-piece glass and brass seal, can help reduce radio frequency interference, regulates spark energy for long electrode life, and helps protect against high combustion pressures
  • Pure copper core provides great heat transfer and helps maximize plug durability
  • Platinum on center electrode enables superior spark characteristics and can reduce voltage requirements of the ignition system
  • Ribless insulator helps optimize plug to boot sea
  • Some ACDelco Gold parts may have formerly appeared as ACDelco Professional
  • Premium aftermarket replacement part
  • Manufactured to meet specifications for fit, form, and function for General Motors vehicles as well as most makes and models
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ACDelco – Iridium Spark Plug: Original Equipment Replacement (Part No.41-162)

Iridium Spark Plug: Original Equipment Replacement

from

$11.99
ACDelco GM Original Equipment Iridium Spark Plugs are designed, engineered, and tested to rigorous standards, and are backed by General Motors. They are our latest in spark plug technology and an exact replacement for your vehicle’s original components. Iridium composition provides a high melting point and great strength, and provides excellent wear resistance and durability. ACDelco GM Original Equipment parts are the true OE parts installed during the production of or validated by General Motors for GM vehicles. Some ACDelco GM Original Equipment parts may have formerly appeared as GM Genuine Parts (OE) or ACDelco Professional.

Product Features:
  • Iridium is the latest in spark plug technology and is an exact replacement for vehicles’ original components
  • Iridium composition provides a high melting point and great strength, helps to provide excellent wear resistance and durability
  • Iridium offers excellent engine idle stability, reliable cold starting, quick acceleration and smooth performance
  • Three Piece Fired in Suppressor seal meters spark energy for long electrode life, helps prevent combustion leakage and helps block radio frequencies that can affect vehicle electronics
  • Iridium plugs are laser-welded which provides precision welds, reduces excess debris and wear rate, thus increasing durability
  • Some ACDelco GM Original Equipment parts may have formerly appeared as GM Genuine Parts (OE) or ACDelco Professional
  • ACDelco GM Original Equipment parts are designed, engineered and tested to rigorous standards, and are backed by General Motors.
  • GM Engineers design and validate OE parts specifically for your Chevrolet, Buick, GMC, or Cadillac vehicle
  • GM regularly updates production and service part designs to integrate new materials and technologies
  • Resistor Type: Equipped with a resistor to help reduce radio frequency interference, ensuring smooth engine performance.
  • Tapered Seat Type: Features a tapered seat type for a secure fit and reliable performance in your vehicle.
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Autolite Iridium – Iridium XP Finewire Spark Plug: Improved Durability, More Focused Ignition (Part No.XP5245)

Iridium XP Finewire Spark Plug: Improved Durability, More Focused Ignition

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$9.99
Our best spark plug! Autolite has over 100 years of engineering experience and has sold over 11 billion plugs. Designed and engineered in the USA, the Autolite Iridium XP spark plugs feature an iridium-enhanced 0.6mm finewire design and patented platinum sidewire technology to provide better overall durability and a more focused ignition for enhanced ignitability and performance. Features double Iridium-enhanced alloy technology center electrode for improved durability and wear resistance.

Product Features:
  • 0.6 mm finewire design improves ignitability
  • Patented V-trimmed platinum sidewire technology resists wear
  • OE equivalent design is engineered for every engine
  • Designed for better overall durability with virtually no gap erosion
  • Double Iridium-Enhanced Alloy Technology Center Electrode: Offers improved durability and wear resistance.
  • Designed and Engineered in the USA: Reflects over 100 years of Autolite’s engineering experience.
  • Tapered Seat Type: Ensures a secure fit and optimal performance.
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FAQs for Workhorse W42 Spark Plugs

What are the most popular Spark Plugs for the Workhorse W42?

With 2 brands you can trust, our most popular Spark Plugs for the Workhorse W42 are:
Iridium Spark Plug: Original Equipment Replacement
from $11.99
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Iridium Spark Plug: Original Equipment Replacement
Spark Plugs
Rapidfire Spark Plug
from $7.99
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Rapidfire Spark Plug
Spark Plugs

What are the best aftermarket Spark Plugs for the Workhorse W42?

See what past customers had to say about our highest-rated Spark Plugs for the Workhorse W42: