2025 Jeep Cherokee Spark Plug Type & Gap

Quick reference

Why the right plug matters

Choosing the correct spark plug for your 2025 Jeep Cherokee is more critical than you might think. Spark plugs are not "one size fits all" components; they are engineered specifically for your engine's operating characteristics. The wrong spark plug can lead to reduced fuel economy, misfires, poor acceleration, and even engine damage.

Two key factors are heat range and electrode material:

• Heat Range: Spark plugs are designed with a specific heat range, which dictates their ability to dissipate heat. A "hot" plug retains more heat in its tip, while a "cold" plug transfers heat more quickly to the cylinder head. An incorrect heat range can lead to pre-ignition (if too hot) or fouling (if too cold), both detrimental to engine performance and longevity.
• Electrode Metal: The material of the electrode significantly impacts plug life and performance.
  • Iridium: The most durable and expensive option, iridium plugs offer exceptional longevity (often 100,000 miles or more) and consistent, powerful sparks due to their fine-wire electrode. They are ideal for modern engines and often specified as OEM.
  • Platinum: Platinum plugs provide good durability (typically 60,000-100,000 miles) and improved performance over copper plugs. They are a common OEM choice for many vehicles.
  • Copper: While offering excellent conductivity and a strong spark, copper plugs have the shortest lifespan (around 30,000 miles) due to their softer electrode material. They are usually found in older vehicles or those with specific performance requirements.

How to gap a spark plug

Properly gapping a spark plug ensures the ideal distance between the center and ground electrodes for a strong, consistent spark. Even if your plugs are "pre-gapped," always double-check the setting.

To gap a spark plug:

1. Use the right tool: A wire-type spark plug gapping tool is preferred over a ramp-style tool, as the latter can damage fine-wire electrodes.
2. Check the gap: Slide the correct size wire gauge between the electrodes. There should be a slight drag.
3. Adjust if necessary: If the gap is too small, gently bend the ground electrode outwards with the gapping tool. If it's too large, carefully tap the ground electrode on a hard, non-abrasive surface.
4. Re-check: Always re-check the gap after adjusting.

Replacement procedure tips

While specific procedures may vary for the 2025 Jeep Cherokee (details for which are not yet available), here are general tips for modern vehicles, often employing coil-on-plug ignition systems:

• Coil-on-Plug Removal: Most modern engines use individual ignition coils mounted directly on top of each spark plug. Carefully disconnect the electrical connector and gently twist and pull to remove the coil. Avoid yanking on the wires.
• Anti-Seize Debate: There's ongoing debate about using anti-seize compound on spark plug threads. Many modern spark plugs have a special coating from the factory that provides anti-seize properties. Applying additional anti-seize can alter the torque readings and potentially lead to over-tightening. Consult your vehicle service manual or the spark plug manufacturer's recommendations. If you do use it, use sparingly and reduce the torque specification by about 10-20%.
• Dielectric Grease on Boots: A small amount of dielectric grease applied to the inside of the spark plug boot (where it contacts the ceramic insulator) can help prevent moisture intrusion and make future removal easier. Avoid getting grease on the electrode tips.

Always allow the engine to cool completely before attempting spark plug removal to prevent damage to the cylinder head threads.

Known issues

As of now, there are no widespread or specific "known issues" regarding spark plugs for the 2025 Jeep Cherokee, as it is a new model year. However, it's always good practice to monitor your vehicle for any signs of misfires, rough idling, or decreased fuel economy, which could indicate a spark plug problem. Issues like cracked porcelain or broken plug shells are often symptoms of improper installation or extreme engine conditions, rather than inherent design flaws.

Need plugs replaced? Find a shop on Repairius.