2024 Ram 3500 Spark Plug Type & Gap

Quick reference

Why the right plug matters

Choosing the correct spark plug for your 2024 Ram 3500 is crucial for optimal engine performance, fuel efficiency, and longevity. The spark plug is responsible for igniting the air/fuel mixture in your engine's cylinders, and a variety of factors influence its effectiveness, including heat range and electrode material.

Heat Range: This refers to the plug's ability to dissipate heat. A "cold" plug dissipates heat quickly, while a "hot" plug retains more heat. Using a plug with an incorrect heat range can lead to issues like pre-ignition (too hot) or fouling (too cold). For the 6.4L HEMI, the specified heat range ensures proper combustion under all operating conditions.

Electrode Material:

• Iridium: These plugs offer the longest lifespan and best performance due to their extremely hard and durable iridium center electrode. They are often original equipment on modern vehicles like the Ram 3500 and can last for 100,000 miles or more, though Mopar specifies a 30,000-mile interval for the 6.4L HEMI.
• Platinum: Platinum plugs provide good durability and performance, typically lasting longer than copper plugs. They are a common choice for vehicles that require extended service intervals.
• Copper: While excellent conductors, copper plugs have a shorter lifespan due to their softer electrode material. They are typically found in older vehicles or high-performance applications where frequent replacement is expected.

For your 2024 Ram 3500 with the 6.4L HEMI, the OEM specified spark plug is a high-quality, long-lasting plug designed to meet the demands of this powerful engine.

How to gap a spark plug

The gap of a spark plug is the distance between the center and ground electrodes. An accurately gapped plug ensures a strong, consistent spark. While many modern spark plugs, especially those for newer vehicles, come "pre-gapped" from the factory, it's always a good practice to verify the gap, especially for copper plugs that might be bent in transit.

To gap a spark plug, you'll need a spark plug gapping tool, which can be a coin-style or wire-style gauge. For precision, a wire-style gauge is recommended.

1. Consult the specifications: Always refer to the manufacturer's recommended gap for your specific engine (0.032 in / 0.8 mm for the 6.4L HEMI).
2. Use the correct tool: Carefully slide the appropriate wire gauge or feeler blade into the gap. It should slide in with slight resistance.
3. Adjust if necessary:
   • If the gap is too small, use the gapping tool to gently pry the ground electrode out a tiny amount. Be very careful not to bend the center electrode.
   • If the gap is too large, gently tap the ground electrode on a hard surface to close the gap. Again, work slowly and in small increments.
4. Re-check: Once adjusted, re-check the gap to ensure it meets the specifications.

Never attempt to force a gapping tool between the electrodes of an iridium or platinum plug, as this can damage the delicate electrode tip. If these plugs are not correctly gapped, it