2024 Chevrolet Silverado 1500 — Spark Plug Type, Gap & Torque

Quick reference

Note: GM frequently supersedes part numbers. Always verify the exact OEM plug part number by VIN in the GM EPC or service information. Never substitute heat range or reach without confirmation.

Why the right plug matters

Choosing the correct spark plug is about more than thread size. Heat range, projected tip design, and electrode material all affect combustion stability, detonation resistance, and coil stress—especially on direct-injected and turbocharged engines like the L3B.

• Heat range: Too hot can cause pre-ignition; too cold can foul. GM calibrates heat range per engine (and sometimes per calibration update). Stick with the OE heat range unless directed otherwise by service bulletins.
• Electrode material:
  • Iridium (OE on Silverado gas engines) offers the longest life and strongest spark at wide gaps with minimal coil load—ideal for the ~100k-mile service interval.
  • Platinum is serviceable but generally shorter life (~60k miles) on high-energy coil-on-plug systems.
  • Copper/nickel fires well but erodes quickly; consider it for short-interval racing or diagnostics, not long-term street use.

How to gap a spark plug

Most OE iridium plugs for the 2024 Silverado arrive pre-gapped. It’s good practice to confirm:

1. Use a wire-style gap gauge (avoid wedge coins that can damage fine-wire electrodes).
2. Measure between ground strap and center electrode.
3. If adjustment is required, very lightly bend the ground strap only. Do not pry on or strike the iridium center.
4. Recheck after any adjustment. On turbo engines (L3B), even small changes in gap can affect misfire under boost—stick to spec.

Replacement procedure tips (2024 Silverado)

All 2024 Silverado gasoline engines use coil-on-plug ignition; there’s no distributor.

• Preparation: Work on a cool engine. Remove the engine cover. Blow debris from plug wells with compressed air to keep grit out of the cylinders.
• Coil removal: Disconnect the electrical connector, remove the coil hold-down (usually 10 mm), and twist the coil boot to break it free before lifting out.
• Plug removal: Use a quality 5/8-inch spark plug socket with a swivel and extensions as needed. Break loose smoothly; if resistance feels abnormal, pause and apply a brief penetrating oil soak, then work the plug out in small turns.
• Thread prep: GM’s OE ACDelco plugs are nickel-plated for anti-corrosion; install dry. Anti-seize is not recommended by GM. If you choose to use it against guidance, reduce torque by ~20% to avoid over-stretching threads.
• Installation: Start each plug by hand at least 5 full turns. Torque to spec (see table). Do not exceed.
• Boots and coils: Inspect boots for oil or carbon tracking. A pea-sized dab of dielectric grease inside the boot lip helps future service and seals out moisture. Reinstall coils and connectors; clear any DTCs if present.

Service interval: Under normal service, OE iridium plugs are ~100,000 miles (160,000 km). Severe duty—extensive idling, heavy towing, dusty environments, or performance tuning—may justify earlier inspection/replacement (e.g., 60,000–80,000 miles).

Known issues (applicability to 2024 Silverado)

• Two-piece plug breakage (Ford 3-valve 5.4L/4.6L) — Not applicable. GM Silverado gas engines use one-piece plugs and are not prone to shell separation.
• Ion-sensing coil requirements — Not applicable to 2024 Silverado. These engines use conventional resistor plugs matched to GM specs.
• General best practice: Aluminum cylinder heads can gall threads if plugs are over-torqued or removed hot. Always service cold and torque correctly to avoid damaged threads.
• Diesel note: The 3.0L Duramax LZ0 uses glow plugs, not spark plugs. Diagnosis and service procedures are entirely different.

If you’re chasing a misfire, always pair plug inspection with a quick coil swap test and a look at fuel trims/injector balance on the DI V8s; that can save you from replacing good parts.

Need plugs replaced? Find a shop on Repairius.