2017 Jeep Wrangler Spark Plug Type & Gap

Quick reference

Why the right plug matters

Spark plugs are vital for your engine's performance, fuel economy, and emissions. Using the correct spark plug for your 2017 Jeep Wrangler's 3.6L Pentastar V6 engine is crucial. The engineers at Jeep specified a very particular plug design to work optimally with the engine's combustion characteristics.

• Heat Range: The heat range of a spark plug indicates its ability to dissipate heat from the combustion chamber. A plug that's too "cold" can foul easily, while one that's too "hot" can lead to pre-ignition and engine damage. The NGK 94006 (LZKAR7AP-11) (or its Mopar equivalent) is designed with the precise heat range for your Pentastar V6, ensuring efficient combustion and preventing issues.
• Electrode Metal: Modern engines like the Pentastar V6 typically utilize long-life spark plugs made with precious metals. The OEM plugs for your 2017 Wrangler are iridium-tipped. Iridium is incredibly hard and has a very high melting point, allowing for a finer wire center electrode. This design provides a more focused spark, improved ignitability, and significantly extends the plug's service life compared to older platinum or copper plugs. While copper plugs offer excellent conductivity, their lifespan is much shorter, and they are not suitable for this engine.

Using a plug with a different design or material can lead to misfires, reduced fuel efficiency, increased emissions, and even costly engine damage in the long run. Stick with the iridium plugs specified by the manufacturer.

How to gap a spark plug

While many modern iridium spark plugs come pre-gapped from the factory, it's always a good practice to double-check the gap before installation. Even a slight variation can impact performance. For your 2017 Jeep Wrangler, the correct gap is 0.043 inches (1.1 mm).

1. Obtain a Gap Tool: Use a wire-type spark plug gap gauge for iridium plugs. Avoid using coin-style or ramp-style gauges, as they can damage the delicate iridium tip.
2. Measure the Gap: Carefully slide the correct wire gauge through the electrode gap. There should be a slight drag.
3. Adjust (if necessary): If the gap is too small, gently pry open the ground electrode using the adjustment tool on the gauge. If the gap is too large, carefully tap the ground electrode on a clean, hard surface to close it slightly. Always adjust only the ground electrode, never bend the center electrode.
4. Re-Measure: Confirm the gap is correct before installation.

Replacement procedure tips

Replacing spark plugs on your 2017 Jeep Wrangler's 3.6L Pentastar V6 is a manageable DIY task, but a few tips can make it smoother:

• Access: The Wrangler's engine bay can be a bit tight. You'll likely need to remove the air intake tube and possibly detach some wiring harnesses to gain better access to the rear bank of spark plugs. Consider removing the front wheels and inner fender liners for easier access to the coil packs on some models, though it's often not necessary. Having a good set of wobble extensions and universal joints for your ratchet will be invaluable.
• Coil-on-Plug Removal: The Pentastar V6 uses coil-on-plug ignition. Each spark plug has its own individual ignition coil. Carefully disconnect the electrical connector from each coil pack, then firmly pull the coil pack straight up to remove it from the spark plug well. Avoid twisting or yanking, as this can damage the coil boot or connector.
• Anti-Seize Debate: There is ongoing debate about using anti-seize on spark plug threads. For spark plugs with nickel-plated shells, like the OEM plugs for your Wrangler, it is generally not recommended to use anti-seize. The nickel plating acts as an anti-seize agent itself, and adding more can lead to over-torquing the plugs, damaging the cylinder head threads, or affecting the plug's heat range. Follow the manufacturer's torque specifications precisely.
• Dielectric Grease: Apply a small amount of dielectric grease inside the spark plug boot (the rubber part of the coil pack that slides over the plug). This helps seal out moisture, prevents corrosion, and makes future removal easier.
• Torque Wrench is a Must: Always use a torque wrench to tighten spark plugs to the specified 13 lb-ft (18 Nm). Overtightening can strip cylinder head threads or damage the spark plug, while undertightening can lead to combustion gas leaks and misfires.

Known issues

Fortunately, the 3.6L Pentastar V6 in the 2017 Jeep Wrangler doesn't have any widespread, engine-specific "known issues" regarding spark plug breakage or unique ignition complications like the Ford 3-valve 2-piece plugs or certain GM ionization-sensing coils. As long as you use the correct OEM or specified aftermarket iridium plugs and follow proper installation procedures, you should have a straightforward replacement experience.

Need plugs replaced? Find a shop on Repairius.