2019 Chevrolet Silverado 1500 Spark Plug Type & Gap

Quick reference

Why the right plug matters

Choosing the correct spark plug for your 2019 Chevrolet Silverado 1500 is crucial for optimal engine performance, fuel efficiency, and longevity. Spark plugs play a vital role in igniting the air-fuel mixture in your engine's combustion chambers. Using the wrong plug can lead to misfires, reduced power, poor fuel economy, and even costly engine damage.

Several factors determine the “right” spark plug, including its heat range, electrode material, and design. The heat range refers to a plug's ability to dissipate heat. A plug that's too "hot" (dissipates heat slowly) can lead to pre-ignition and detonation, while a plug that's too "cold" (dissipates heat quickly) can foul up with carbon deposits. Modern engines like those in the 2019 Silverado are designed for specific heat ranges to ensure proper combustion and prevent these issues.

The electrode material also significantly impacts performance and lifespan. Iridium and platinum plugs, like the OEM ACDelco 41-162, are designed for extended service intervals due to their exceptional durability and resistance to wear. These precious metals allow for finer electrode tips, which produce a more consistent and powerful spark. Copper plugs, while excellent conductors, wear out much faster and are not typically recommended for modern engines that require longer service intervals. For your 2019 Silverado 1500, always stick with iridium-tipped plugs as specified by the manufacturer.

How to gap a spark plug

While most modern iridium-tipped spark plugs come pre-gapped, it's always a good practice to double-check the gap before installation, especially if you're not using OEM plugs. The gap is the distance between the center and ground electrodes. An incorrect gap can lead to an inconsistent spark and engine performance issues.

To gap a spark plug, you'll need a wire-type spark plug gapping tool. Never use a disc-style gapping tool on fine-wire iridium or platinum plugs, as it can damage the delicate electrode tip. Carefully slide the correct thickness wire gauge (0.040 inches for your Silverado) into the gap. If the gap is too small, gently bend the ground electrode outwards with the tool. If the gap is too wide, carefully tap the ground electrode on a hard, non-abrasive surface to close it slightly. Be extremely cautious not to touch or damage the center electrode during this process.

Replacement procedure tips

Replacing spark plugs on your 2019 Chevrolet Silverado 1500 is a straightforward but detail-oriented task. All engine options (4.3L V6, 5.3L V8, 6.2L V8) utilize a coil-on-plug (COP) ignition system, meaning each spark plug has its own individual ignition coil mounted directly over it.

1. Preparation: Ensure the engine is cool before starting. Disconnect the negative terminal of your battery. Gather your tools, including a spark plug socket (typically 5/8-inch, swiveling is helpful), ratchet, extensions, torque wrench, and dielectric grease.
2. Coil Pack Removal: Carefully unplug the electrical connector from each ignition coil. Then, unbolt and remove the coil pack. Some models may have a small retainer clip that needs to be released.
3. Spark Plug Removal: Use a proper spark plug socket to remove the old plugs. Twist counter-clockwise. Take care to avoid dropping debris into the combustion chamber. Inspect the old plugs for signs of wear or issues, which can provide insight into your engine's health.
4. Anti-Seize Debate: There's ongoing debate regarding the use of anti-seize on spark plug threads. For spark plugs with nickel-plated shells, like the OEM ACDelco plugs for your Silverado, anti-seize is generally NOT recommended by the manufacturer. The nickel plating provides sufficient anti-seize properties, and adding more can lead to over-torquing and damage to the cylinder head threads or even inaccurate torque readings. Follow ACDelco recommendations for factory plugs.
5. Installation: Hand-thread the new spark plugs into the cylinder head to prevent cross-threading. Once snug, use a torque wrench to tighten them to the specified 11 lb-ft (15 Nm). Over-tightening can easily damage the cylinder head threads or the spark plug itself.
6. Dielectric Grease: Apply a small amount of dielectric grease inside the spark plug boot (the part of the coil pack that slides over the spark plug). This helps seal out moisture, prevents corrosion, and makes future removal easier. Reinstall the coil packs, plug in the electrical connectors, and reconnect the battery.

Known issues

Fortunately, the 2019 Chevrolet Silverado 1500 typically does not suffer from widespread, notorious spark plug-related issues like the Ford 3-valve engine's propensity for broken two-piece plugs. The coil-on-plug design is generally robust, and the engines are not known for ionization-sensing coil problems reminiscent of some earlier GM 5.3L engines.

However, like any vehicle, consistent maintenance is key. Ignoring regular spark plug replacement intervals can lead to misfires, reduced fuel economy, and increased emissions. Using incorrect spark plugs or improper gapping can also cause preventable problems.

Need plugs replaced? Find a shop on Repairius.