2016 Chevrolet Silverado 2500HD Spark Plug Specs, Gap & Torque

If you are driving a 2016 Chevrolet Silverado 2500HD with the 6.0L Vortec V8 gasoline engine, maintaining a healthy ignition system is crucial for towing, hauling, and daily reliability. As an ASE-certified master technician, I’ve serviced countless heavy-duty trucks, and keeping your spark plugs fresh is one of the easiest ways to ensure optimal performance, fuel economy, and idle smoothness.

(Note: If your Silverado 2500HD is equipped with the 6.6L Duramax turbo-diesel, your engine uses glow plugs, not spark plugs.)

Quick reference

Here are the factory specifications and approved aftermarket alternatives for the 2016 Chevy Silverado 2500HD 6.0L V8:

Why the right plug matters

Modern General Motors engines, including the 6.0L V8 L96, are engineered to run on precise ignition parameters. Using the correct spark plug ensures the heat range matches the engine's operating temperature, preventing pre-ignition (pinging) or carbon fouling.

The OEM ACDelco 41-162 is an iridium spark plug. Iridium is significantly harder and more durable than platinum or standard copper, allowing for the extended 97,500-mile service interval. Copper plugs provide great conductivity but will wear out in as little as 20,000 miles. Platinum is a middle ground. For this heavy-duty workhorse, stick to OEM ACDelco or high-quality NGK/Denso iridium plugs.

How to gap a spark plug

Even if your new iridium plugs come "pre-gapped," you must verify the gap before installation to ensure they weren't dropped or bumped during shipping.

1. Use the right tool: Use a wire-style feeler gauge rather than a cheap coin-style gauge.
2. Be gentle: Iridium center electrodes are brittle. Never pry against the center electrode!
3. Adjusting the gap: If the gap is too tight, use the adjustment notch on your gap tool to lightly bend the ground strap outward. If it’s too wide, tap the back of the ground strap gently on a soft wood block to close it. For the 6.0L V8, you are aiming for exactly 0.040 inches (1.01 mm).

Replacement procedure tips

The 6.0L V8 uses a coil-near-plug (often grouped with coil-on-plug) ignition system, where a short spark plug wire connects an individual ignition coil to each spark plug.

• Boot removal: Twist the spark plug boot side-to-side to break the seal before pulling. Pulling directly on the wire can break the internal conductor.
• The anti-seize debate: General Motors and ACDelco specifically advise against using anti-seize compound on these spark plug threads. The factory plugs feature a special zinc/nickel coating that prevents seizing. Adding anti-seize acts as a lubricant, which can easily cause you to over-torque the plug and damage the aluminum cylinder head.
• Dielectric grease: Apply a small dab of dielectric grease to the inside of the spark plug boot before reinstallation. This prevents moisture intrusion, stops high-voltage arcing (tracking), and makes the boot much easier to remove during the next service.

Known issues

While the 6.0L V8 doesn't suffer from the infamous two-piece spark plug breakage seen in some older Ford 3-valve engines, there are a few GM-specific quirks to be aware of:

• Metal heat shields: The factory spark plug wire boots have metal heat shields surrounding them. These shields can become stuck to the cylinder head or get sharp edges from rust. Wear mechanic's gloves to avoid slicing your hands while wrestling off a stubborn wire.
• Cylinder 8 access: The rearmost spark plug on the passenger side (Cylinder 8) is notorious for being difficult to reach due to the HVAC box and firewall clearance. Use a combination of a stubby spark plug socket, a universal joint (swivel), and varying lengths of short extensions to get the right angle.

Need plugs replaced? Find a shop on Repairius.