2020 Ram 1500 Spark Plug Specifications

Quick Reference: 2020 Ram 1500 Spark Plugs

Note: The 5.7L HEMI uses two spark plugs per cylinder, for a total of 16. The EcoDiesel uses glow plugs for starting assistance, which are different from spark plugs.

Why the Right Spark Plug Matters

Choosing the correct spark plug is critical for engine performance, fuel economy, and longevity. It's not just about finding a plug that fits; it's about matching the plug's characteristics to the engine's demands.

• Heat Range: This is the most critical factor. The heat range determines how quickly the spark plug tip dissipates heat. A "hot" plug transfers heat slowly, burning off carbon deposits at low speeds, while a "cold" plug transfers heat quickly to prevent overheating and pre-ignition under high load. The plugs specified by Ram are engineered for the exact heat range your engine requires.
• Electrode Material: The 2020 Ram 1500 engines use long-life Iridium-tipped spark plugs from the factory. Iridium is an extremely hard and dense precious metal, allowing for a very fine center electrode. This fine tip requires less voltage to create a spark, provides a more focused and consistent spark, and is highly resistant to wear. While cheaper copper or platinum plugs might fit, they will have a significantly shorter service life and may not perform as well, potentially reducing fuel economy and power. For a modern engine like those in the Ram, sticking with the specified Iridium plug is the best choice.

How to Gap a Spark Plug

Even though most premium plugs like the OEM NGK units come pre-gapped, it is essential to verify the gap before installation. Shipping and handling can easily close the gap.

1. Use the Right Tool: Use a dedicated spark plug gapping tool, either a feeler gauge style or a ramped wire gauge. Avoid the simple "coin-style" disc gappers, as they can put pressure on the fragile center electrode and damage it.
2. Check the Gap: For the 3.6L and 5.7L engines, slide the 0.043-inch gauge between the center and ground electrodes. It should pass through with very light drag. If it's too loose or too tight, it needs adjustment.
3. Adjust Carefully: To adjust, never pry against the center electrode. Instead, gently bend the ground electrode (the L-shaped piece of metal hook) up or down using the slot on your gapping tool or a pair of needle-nose pliers. Make tiny adjustments and re-check until the gap is perfect.

Replacement Procedure Tips for 2020 Ram 1500

The 2020 Ram 1500 uses a modern coil-on-plug (COP) ignition system, which simplifies the replacement process.

• Coil-on-Plug Removal: Each spark plug has its own ignition coil sitting directly on top of it. To access the plug, first disconnect the low-voltage electrical connector from the coil. Then, unbolt the coil (typically a single 10mm bolt) and gently twist and pull it straight up and out of the spark plug well. The rubber boot can sometimes stick to the plug's porcelain, so a firm, steady pull is key.
• The Anti-Seize Debate: Modern NGK spark plugs feature a trivalent plating that acts as an anti-seize and release agent. NGK and Mopar explicitly advise against using additional anti-seize compound on these plugs. Applying it can act as a lubricant, leading you to overtighten the spark plug, which can stretch the plug's threads or damage the cylinder head. Install the plugs dry into a clean, dry cylinder head.
• Dielectric Grease: While anti-seize is a no-go, applying a small amount of dielectric grease to the inside of the ignition coil boot is highly recommended. This grease prevents voltage leaks, makes future coil removal much easier by preventing the boot from sticking to the new plug, and helps seal out moisture.

Known Issues

While older truck engines had well-documented spark plug issues (like the infamous Ford 3-valve two-piece plugs that would break in the head), the engines in the 2020 Ram 1500 are generally robust in this area. There are no widespread, common issues related to spark plug breakage or difficult removal on the 3.6L Pentastar, 5.7L HEMI, or 3.0L EcoDiesel of this model year, provided the job is done with the engine cool and the plugs are not overtightened.

Need plugs replaced? The job requires precision and the right tools. Find a trusted, local shop on Repairius to ensure your Ram runs smoothly for the next 100,000 miles.