2016 Ford F-150 Spark Plug Replacement Guide

Quick Reference

Note: Always verify the exact spark plug part number and gap specification for your specific engine and model year using your vehicle's owner's manual or a reputable parts catalog.

Why the right plug matters

Choosing the correct spark plugs for your 2016 Ford F-150 is crucial for optimal engine performance, fuel efficiency, and longevity. Spark plugs are not a universal component, and using the wrong type can lead to a host of problems.

Heat Range

Spark plugs are designed with a specific "heat range," which refers to their ability to dissipate heat from the combustion chamber. A plug that is "too hot" (dissipates heat slowly) can lead to pre-ignition and detonation, which can severely damage engine components. Conversely, a plug that is "too cold" (dissipates heat too quickly) can foul up with carbon deposits, leading to misfires and poor performance. Ford engineers carefully select the heat range for each engine to ensure efficient combustion and prevent issues.

Electrode Metal (Iridium vs. Platinum vs. Copper)

Modern spark plugs primarily use iridium or platinum center electrodes due to their durability and long lifespan.

• Iridium is incredibly hard and has a very high melting point, allowing for very fine electrodes that produce a strong, consistent spark. Iridium plugs are typically rated for 100,000 miles or more and are the standard for most modern vehicles, including the 2016 F-150.
• Platinum plugs offer similar benefits to iridium, though they may have a slightly shorter lifespan. Double platinum plugs use platinum on both the center and ground electrodes for extended durability.
• Copper plugs have a significantly shorter lifespan (typically 10,000-30,000 miles) but are excellent conductors of electricity. They are rarely used in modern production vehicles like the 2016 F-150 due to their limited lifespan, but can be found in some high-performance or modified applications where frequent changes are desired.

Using the factory-recommended iridium spark plugs for your 2016 F-150 is essential to meet the specified service intervals and maintain peak engine performance.

How to gap a spark plug

While most modern iridium spark plugs come pre-gapped from the factory, it's always a good idea to double-check the gap before installation, especially if you're dealing with a sensitive engine like the EcoBoost. Never attempt to "gap" a fine-wire iridium or platinum plug with a traditional coin-style gapping tool, as you can easily damage the delicate electrode.

For iridium and platinum plugs, use a wire-style spark plug gap gauge. Carefully slide the correct diameter wire through the gap. If adjustment is needed, gently bend the ground electrode only. Avoid putting any stress on the center electrode. Most 2016 F-150 engines require a gap between 0.030-0.033 inches (0.76-0.84 mm) for the EcoBoost engines and 0.049-0.053 inches (1.24-1.35 mm) for the naturally aspirated engines. Refer to the table above for your specific engine.

Replacement procedure tips

Replacing spark plugs on a 2016 Ford F-150 is a manageable DIY job for those with some mechanical experience. All 2016 F-150 engines utilize a coil-on-plug (COP) ignition system, meaning each spark plug has its own individual ignition coil directly mounted above it.

1. Preparation: Gather your tools: a torque wrench, spark plug socket (typically 5/8" or 9/16"), various extensions and swivels, a ratchet, dielectric grease, anti-seize (optional, see below), and a can of compressed air.
2. Access: Depending on your engine, you may need to remove engine covers, intake tubing, or even the intake manifold (particularly on the 3.5L EcoBoost and 2.7L EcoBoost for rear bank plugs) to gain access to all the spark plugs.
3. Coil-on-Plug Removal: Disconnect the electrical connector from each coil. Carefully release the locking tab and pull the connector straight off. Then, unbolt the coil (usually a 7mm or 8mm bolt) and gently twist and pull the coil straight up to remove it from the spark plug well. Avoid yanking on the wires.
4. Clean Plug Wells: Before removing the old plugs, use compressed air to blow out any dirt or debris that may have collected in the spark plug wells. This prevents contaminants from falling into the combustion chamber when the old plug is removed.
5. Remove Old Plugs: Use your spark plug socket and ratchet to carefully loosen and remove the old spark plugs. Pay attention to how tight they feel and inspect the old plugs for any signs of wear, fouling, or damage.
6. Anti-Seize Debate: There is ongoing debate about using anti-seize compound on spark plug threads, especially with nickel-plated plugs. Ford, and many spark plug manufacturers, often advise against it. Nickel-plated plugs are designed to prevent seizing without additional compounds, and anti-seize can act as an insulator, altering torque readings and potentially leading to over-tightening or incorrect electrical grounding. If you choose to use it, apply a very thin amount to the threads, making sure it doesn't get on the electrode or porcelain. And reduce your torque specification by about 10-20%.
7. Dielectric Grease: Apply a small amount of dielectric grease inside the boot of each ignition coil. This helps seal out moisture, prevents corrosion, and makes future coil removal easier. Do not apply dielectric grease to the spark plug threads or electrode.
8. Install New Plugs: Carefully thread the new spark plugs into the cylinder heads by hand first to avoid cross-threading. Once finger-tight, use a torque wrench to tighten them to the specified setting (11 lb-ft / 15 Nm for all engines). Do not over-tighten! Over-tightening can damage the spark plug, cylinder head threads, or even crack the porcelain insulator.
9. Reinstall Coils and Components: Reinstall the ignition coils, ensuring they seat properly over the spark plugs. Bolt them down, reconnect electrical connectors, and reassemble any components removed to gain access.

Known Issues

Fortunately, for the 2016 Ford F-150, there are no widespread "known issues" regarding spark plug breakage or unique challenges like the older Ford 3-valve Triton engines (2-piece spark plug breakage) or GM 5.3L ionization-sensing coils.

However, it's important to be aware of general best practices:

• EcoBoost Carbon Buildup: Direct injection engines like the EcoBoost can be prone to carbon buildup on the intake valves, but this doesn't directly affect the spark plugs' physical integrity. Consistent use of top-tier fuel and proper maintenance can help mitigate this.
• Cracked Porcelain: While not a "known issue" for the 2016 F-150 specifically, cracked porcelain on a spark plug can occur if the plug is dropped, mishandled, or over-tightened during installation. Always handle new plugs with care.

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