2017 Chevrolet Silverado 2500HD Spark Plug Type & Gap

Quick reference

Why the right plug matters

Choosing the correct spark plug for your 2017 Chevrolet Silverado 2500HD 6.0L V8 is crucial for optimal engine performance, fuel efficiency, and longevity. The spark plug's primary role is to ignite the air-fuel mixture in the combustion chamber. If the plug isn't right, it can lead to misfires, reduced power, poor fuel economy, and potentially even engine damage.

Heat range

Spark plugs are designed with a specific "heat range" that dictates how quickly they transfer heat away from the tip. A plug that's too hot can lead to pre-ignition and detonation, while one that's too cold can cause fouling. The OEM plugs are carefully selected for your engine's operating conditions to maintain the ideal temperature.

Electrode metal

• Iridium: The most common type for modern vehicles due to its extreme durability and fine-wire electrode, which provides a stronger, more focused spark. OEM plugs for your Silverado 6.0L are typically iridium.
• Platinum: Another long-lasting option, often found in older vehicles or as an upgrade from copper. Platinum plugs offer good performance and lifespan.
• Copper: While excellent conductors, copper plugs have a shorter lifespan due to their softer material and thicker electrode. They are generally not recommended for modern engines designed for iridium or platinum.

How to gap a spark plug

The gap between the spark plug's center and ground electrodes is critical for a strong and consistent spark. While most iridium and platinum plugs come pre-gapped from the factory, it's always a good idea to double-check the gap before installation. For the 6.0L V8, the gap should be 0.040 inches (1.0 mm).

Use a wire-style spark plug gap gauge for iridium and platinum plugs. Avoid using coin-style or ramp-style gauges, as they can damage the delicate fine-wire electrode. If adjustment is needed, gently bend the ground electrode with the tool, being careful not to touch the center electrode.

Replacement procedure tips (6.0L V8)

Replacing spark plugs on your 2017 Silverado 2500HD 6.0L V8 is a manageable DIY task for most mechanically inclined individuals.

Coil-on-plug removal

Your 6.0L V8 uses a coil-on-plug (COP) ignition system. Each spark plug has its own ignition coil mounted directly above it. To access the plugs, you'll need to:

1. Disconnect the electrical connector from each coil.
2. Remove the bolt securing the coil to the valve cover.
3. Gently pull up on the coil to remove it from the spark plug. The coil boot might offer some resistance due to suction.

Anti-seize debate

There's a long-standing debate about using anti-seize on spark plug threads. For spark plugs with nickel-plated shells (like most modern OEM plugs), anti-seize is generally not recommended. The nickel plating acts as an anti-seize itself and applying additional anti-seize can lead to over-torquing the plugs, potentially damaging the cylinder head threads.

Dielectric grease on boots

Applying a small amount of dielectric grease inside the spark plug boots (the part that connects to the spark plug) can help prevent moisture intrusion, improve electrical connection, and make future removal easier. Be sparing with its application; too much can cause issues.

Known issues

Fortunately, the 6.0L V8 engine in your 2017 Chevrolet Silverado 2500HD is not known for specific spark plug related design flaws like the notorious Ford 3-valve engine's breaking two-piece plugs. As long as you use the correct OEM or recommended aftermarket plugs and adhere to the specified replacement intervals and torque specs, you should experience trouble-free operation.

Need plugs replaced? Find a shop on Repairius.