2024 Jeep Grand Cherokee Spark Plug Type, Gap & Torque Guide

As an ASE-certified master technician, I’ve serviced countless Jeep Grand Cherokees. For the 2024 model year, the Grand Cherokee (WL generation) primarily utilizes the tried-and-true 3.6L Pentastar V6 and the advanced 2.0L Turbo PHEV found in the 4xe models. Choosing the exact spark plug, maintaining the precise gap, and torquing them correctly are non-negotiable steps to ensure peak performance, fuel efficiency, and emissions compliance.

Below is your comprehensive guide to getting the spark plug replacement right the first time on a 2024 Jeep Grand Cherokee.

Quick reference

Note: The Grand Cherokee no longer uses the 5.7L Hemi V8 in the standard two-row configuration for 2024. Always cross-reference the exact Mopar part number with your vehicle’s VIN.

Why the right plug matters

Modern engines are incredibly sensitive to combustion dynamics. The 2024 Grand Cherokee requires specific Iridium-tipped spark plugs. Iridium offers a much higher melting point than platinum or older copper core plugs, ensuring the sharpest possible electrode over a 60,000 to 100,000-mile lifespan.

Heat range is equally critical. Using a plug that runs too hot can lead to pre-ignition (engine knock) and severe piston damage, particularly in the forced-induction 2.0L Turbo 4xe. A plug that runs too cold will rapidly foul with carbon deposits, leading to misfires. Always stick to the OEM heat range—do not "upgrade" to a colder plug unless your engine is heavily modified.

How to gap a spark plug

Most premium iridium spark plugs come pre-gapped from the factory, but you must always verify the gap before installation. Dropped boxes in transit can easily close a gap.

1. Use the right tool: Do not use a cheap coin-style gauge on iridium plugs; sliding it between the electrodes can snap the fragile, wire-thin iridium center electrode. Use a wire-style feeler gauge.
2. Measuring: Gently pass the correct wire size (e.g., 0.043" for the 3.6L) through the gap. It should pass through with a slight "drag."
3. Adjusting: If the gap needs adjustment, use the bending tool on the gauge to carefully pry or tap the ground electrode (the curved top piece). Never apply pressure to the delicate center electrode.

Replacement procedure tips

Both the 3.6L V6 and 2.0L Turbo utilize Coil-on-Plug (COP) ignition systems, meaning there are no distributor caps or standard spark plug wires to deal with.

• Intake Plenum Removal (3.6L V6): The primary hurdle on the Pentastar V6 is that the upper intake manifold (plenum) crosses over the left (driver's side) cylinder bank. You must remove the upper intake plenum to access the three coils and plugs underneath. Have a new set of upper intake manifold gaskets ready before you start the job to prevent vacuum leaks upon reassembly.
• The Anti-Seize Debate: Mopar does not recommend using anti-seize on these specific spark plugs. Modern NGK, Champion, and Denso plugs feature a specialized trivalent metal plating that acts as a release agent. Adding anti-seize acts as a lubricant, which throws off your torque readings and can easily lead to over-tightening and stripping the aluminum cylinder head threads. Install them dry.
• Dielectric Grease: Apply a very small, pea-sized dab of dielectric grease to the inside of the new coil boot (the rubber part). This prevents moisture intrusion and ensures the boot won’t bake and stick to the ceramic porcelain of the plug over the next 100,000 miles.

Known issues

• Spark Plug Tube Oil Leaks: On the 3.6L Pentastar, keep an eye out for engine oil inside the spark plug tubes when you pull the ignition coils. If the coil boot is soaked in oil, the spark plug tube seals in the valve cover are failing. You will need to replace the valve cover gaskets and tube seals to prevent ignition misfires.
• Seized Plugs in High-Mileage Engines: While we don't see the notorious broken plug shell or cracked porcelain issues that plagued the older Ford 3-valve engines, Pentastar plugs left in the engine far past their 100k-mile interval can become stubborn. If a plug feels exceptionally tight upon removal, do not force it. Spray a penetrating oil down the tube, let it soak, and gently work the plug back and forth (loosen a quarter turn, tighten an eighth turn) to safely extract it without destroying the aluminum cylinder head threads.

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