2018 Ford Transit Spark Plug Type & Gap

Quick reference

Engine	OEM Plug PN	Aftermarket (NGK/Denso/Motorcraft)	Gap (in/mm)	Torque (lb-ft / Nm)	Interval
2.3L EcoBoost	DYFS-12-07-AD	N/A	0.027 - 0.031 / 0.7 - 0.8	11 / 15	100,000 miles
3.7L Ti-VCT	BER8ET-10	N/A	0.049 - 0.053 / 1.25 - 1.35	13 / 18	100,000 miles
3.5L EcoBoost	SP-578	N/A	0.027 - 0.031 / 0.7 - 0.8	11 / 15	100,000 miles

Why the right plug matters

Choosing the correct spark plug for your 2018 Ford Transit is crucial for optimal engine performance, fuel efficiency, and longevity. Spark plugs are not a "one-size-fits-all" component, and using the wrong type can lead to a host of problems, from misfires and reduced power to catalytic converter damage.

Heat range

Spark plugs are designed with a specific "heat range" that determines how quickly heat is transferred away from the firing tip. A plug that's too hot can lead to pre-ignition and engine damage, while a plug that's too cold can cause fouling and misfires. Ford engineers carefully select the ideal heat range for your Transit's engine to maintain proper combustion temperatures.

Electrode metal

The electrode material significantly impacts a spark plug's lifespan and performance. The 2018 Ford Transit engines typically utilize iridium or platinum plugs, which offer superior durability and conductivity compared to traditional copper plugs. These precious metals resist wear and erosion, allowing for extended service intervals of up to 100,000 miles.

• Iridium: Extremely hard and durable, offering the longest lifespan and best performance.
• Platinum: A good balance of performance and durability, often used as an OEM choice.
• Copper: Excellent conductivity but wears quickly, requiring more frequent replacement. While not typically used in modern Ford Transit engines as OEM, some aftermarket options may be available for specific applications.

How to gap a spark plug

While most modern iridium and platinum spark plugs come pre-gapped from the factory, it's always a good practice to double-check the gap before installation, especially for the 2018 Ford Transit where precise gaps are critical for proper combustion.

1. Obtain a wire-type gap gauge: Avoid using a ramp-style gauge, as it can damage the delicate iridium or platinum electrode.
2. Verify the correct gap: Consult the "Quick reference" table above for your specific engine.
3. Adjust if necessary: If the gap is too small, carefully bend the ground electrode outwards using the notch on the gap gauge. If the gap is too wide, gently tap the ground electrode on a clean, hard surface to close it. Be extremely careful not to touch or damage the center electrode.

Replacement procedure tips

Replacing spark plugs on your 2018 Ford Transit can be a straightforward DIY task, but there are a few important considerations to ensure a smooth and successful job.

Coil-on-plug removal

All 2018 Ford Transit engines utilize a coil-on-plug (COP) ignition system. This means each spark plug has its own individual ignition coil directly mounted on top of it. To access the plugs, you'll need to:

1. Disconnect the battery: Always disconnect the negative terminal of the battery before working on any electrical components.
2. Disconnect the electrical connector: Gently squeeze the tab on the electrical connector and pull it straight off the ignition coil.
3. Remove the coil hold-down bolt: Use the appropriate socket to remove the bolt securing the ignition coil to the valve cover.
4. Carefully pull the coil: Twist and pull the ignition coil straight up and off the spark plug. Avoid yanking or prying, as this can damage the coil or the spark plug boot.

Anti-seize debate

When it comes to applying anti-seize compound to spark plug threads, there's a long-standing debate. For aluminum cylinder heads, like those found in the 2018 Ford Transit, many manufacturers, including Ford, recommend not using anti-seize. The reason is that anti-seize can act as an insulator, affecting the torque readings and potentially leading to over-tightening and damaged threads.

Ford spark plugs typically have a special coating on the threads that prevents seizing. If you do choose to use anti-seize, apply a very thin coat and reduce the torque specification by approximately 10-20% to compensate for the reduced friction.

Dielectric grease on boots

Applying a small amount of dielectric grease inside the spark plug boot (the part that connects to the top of the spark plug) is highly recommended. This silicone-based grease helps to:

• Prevent moisture intrusion: Keeps water and contaminants out of the spark plug well.
• Aid in removal: Makes it easier to remove the coil boot in the future.
• Improve electrical insulation: Ensures a good electrical connection and prevents arcing.

Known issues

Fortunately, the 2018 Ford Transit engines are not widely known for specific catastrophic spark plug issues like the older Ford 3-valve 2-piece plugs that were prone to breakage. However, always exercise caution and follow proper procedures during removal and installation to avoid common problems such as cross-threading or breaking the porcelain insulator.

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