2024 Chevrolet Suburban Spark Plug Type, Gap, & Torque Specs

Maintaining the performance and fuel efficiency of your 2024 Chevrolet Suburban means staying on top of scheduled maintenance. For the powerful 5.3L and 6.2L EcoTec3 V8 engines powering these full-size SUVs, spark plugs play a critical role in maximizing power, maintaining fuel economy, and ensuring a smooth idle. (Note: The 3.0L Duramax inline-six is a diesel engine and does not use spark plugs).

Whether you are doing the job yourself or just want to be informed before heading to the shop, here is the complete guide to spark plug part numbers, gaps, torque specs, and replacement procedures for the 2024 Chevrolet Suburban.

Quick reference

Note: Always verify exact part numbers with your dealership using your VIN, as GM occasionally supersedes ACDelco part numbers.

Why the right plug matters

Modern GM Gen V V8s utilize direct injection, variable valve timing, and Dynamic Fuel Management. These advanced systems require an incredibly consistent and precise spark.

Factory ACDelco spark plugs for the 2024 Suburban are strictly iridium. Iridium is much harder and more durable than platinum or standard copper. Because the center electrode can be machined to a very fine wire, it requires less voltage to jump the gap, resulting in a highly efficient spark. Using a cheaper platinum or copper plug in this engine will lead to premature wear, engine misfires, and potentially catalytic converter damage. Stick to OEM ACDelco or equivalent premium iridium plugs from NGK or Denso.

How to gap a spark plug

While modern iridium spark plugs typically come pre-gapped from the factory (at 0.038" for the Suburban), you should always verify the gap before installation in case the plug was dropped during shipping.

1. Use the right tool: Use a wire-style feeler gauge rather than a coin-style gapper. Coin gappers can easily snap the brittle, fine-wire iridium center electrode.
2. Check the gap: Gently slide the 0.038" (0.96 mm) wire between the center and ground electrode. It should pass through with a slight drag.
3. Adjusting (if necessary): If the gap is too tight, use the bending tool on the gauge to gently pry the ground strap up. Never pry against the fragile iridium center electrode. If the gap is too loose, lightly tap the ground strap on a hard surface to close it.

Replacement procedure tips

The 2024 Suburban utilizes a coil-on-plug (COP) ignition system where a dedicated ignition coil sits near each cylinder, connected by a short plug wire.

• Clear the area: Before removing the old plugs, use compressed air to blow dirt and debris out of the spark plug wells. You do not want sand falling into your engine cylinders.
• The anti-seize debate: Do not use anti-seize on modern ACDelco or NGK plugs. These plugs feature a special nickel-plated shell designed to prevent seizing in the aluminum cylinder heads. Adding anti-seize acts as a lubricant, which can cause you to over-torque the plug and strip the delicate aluminum threads in your expensive LT-series cylinder heads.
• Dielectric grease: Apply a small dab of dielectric grease to the inside of the spark plug boot before reattaching it. This prevents moisture intrusion, stops voltage leaks, and ensures the boot won't fuse to the ceramic portion of the plug over the next 100,000 miles.
• Torque properly: Tighten the new plugs to exactly 11 lb-ft (15 Nm). Overtightening can stretch the plug or damage the cylinder head.

Known issues

Unlike the infamous Ford 3-valve Triton engines that suffered from two-piece spark plugs snapping off in the block, the modern GM LT architecture is highly reliable in the spark plug department.

However, there is a specific sensitivity to note: GM's advanced ignition system uses the spark plugs for ionization sensing (essentially using the plug as a sensor to detect misfires and knock). Because of this, using aftermarket plugs with different electrical resistance than the factory ACDelco plugs can sometimes confuse the engine computer, leading to phantom misfire codes. For the easiest, most reliable replacement, stick with the factory ACDelco 41-114 or 41-162 iridiums.

Need plugs replaced? Find a shop on Repairius.