2014 Ford F-250 Super Duty Spark Plug Type, Gap & Torque Specs

When it comes time to service your 2014 Ford F-250 Super Duty, one of the most critical maintenance tasks for the 6.2L Boss V8 gas engine is spark plug replacement. As an ASE-certified master technician, I can tell you firsthand that swapping plugs on heavy-duty trucks isn't just about restoring lost fuel economy—it's about protecting your catalytic converters and ensuring peak towing performance under heavy load.

(Note: The 6.7L Power Stroke V8 offered in this model year is a diesel engine and does not use spark plugs.)

Quick reference

Why the right plug matters

Choosing the correct spark plug is more than just making sure the threads fit. The 6.2L V8 in your F-250 requires strict adherence to the factory heat range and electrode material specifications.

• Heat Range: The engine’s combustion chamber temperatures run hot, especially when hauling a heavy trailer up a grade. The spark plug must dissipate heat at the exact rate Ford engineers specified to prevent pre-ignition (pinging) or carbon fouling.
• Electrode Metal: Copper conducts electricity best but wears out rapidly. Platinum lasts longer, but Iridium is the top tier. Iridium is harder and more durable, which is why Motorcraft (and premium aftermarket brands like NGK and Denso) use fine-wire iridium tips for the 6.2L V8. It ensures the plugs easily survive the 100,000-mile service interval without severe electrode erosion.

How to gap a spark plug

Even if your Motorcraft SP-526 or NGK Iridium plugs are advertised as "pre-gapped," you should always verify the gap before installation. Shipping drops can easily close a gap.

1. Use the Right Tool: Use a wire-style gap gauge or a specialized feeler gauge rather than a cheap coin-style gauge, which can snap the fragile iridium center electrode.
2. Check the Gap: Slide the wire gently between the center and ground electrode. For the 6.2L V8, you want exactly 0.041 to 0.045 inches (approx. 1.04 to 1.14 mm).
3. Adjust Carefully: If the gap is too tight, use the bending tool on your gauge to carefully pull back the ground strap. Never lever against the center electrode! If the gap is too wide, gently tap the ground strap on a soft wooden workbench.

Replacement procedure tips

Replacing plugs on the 2014 F-250's 6.2L V8 is a unique experience. Here is what you need to know:

• Sixteen Plugs: The 6.2L Boss V8 uses a twin-spark system, meaning there are 16 spark plugs in total—two per cylinder.
• Coil-on-Plug & Wires: The upper bank of plugs (8) sits directly under the Coil-on-Plug (COP) assemblies. The lower bank of plugs (8) is positioned below the exhaust manifolds and is fired by short spark plug wires running from the upper coils.
• Accessing the Lower Bank: The easiest way to reach the bottom eight plugs is by removing the front wheels and the plastic inner fender liners. It saves you from fighting blind angles from above or below the frame rail.
• Anti-Seize Debate: Ford utilizes a nickel-plated shell on the Motorcraft SP-526. Because of this plating, Ford strictly advises against using anti-seize on the threads, as it alters the torque spec and can lead to over-tightening.
• Dielectric Grease: Always apply a small dab of silicone dielectric grease to the inside of the coil boots and plug wire boots. This prevents moisture intrusion, stops high-voltage tracking, and ensures the boots won't tear during the next plug change.

Known issues

Many truck owners are rightfully traumatized by older Ford trucks (specifically the 5.4L 3-valve engines from 2004-2008) that featured a two-piece spark plug notorious for breaking off inside the cylinder head.

The Good News: The 2014 F-250 6.2L V8 does not use this flawed two-piece design. Broken plug shells and cracked porcelain are incredibly rare on this engine, provided you use the proper spark plug socket (a standard 5/8" magnetic or rubber-insert socket works perfectly) and do not over-torque the plugs. Torque them to a snug 12 lb-ft (16 Nm) on a cold engine, and they will back out smoothly at the next interval.

Need plugs replaced? Find a shop on Repairius.