Motorcraft SP-546 Platinum Spark Plugs OEM PZK14F For F150 F250 5.4L Pack of 8
Motorcraft SP-546 Platinum Spark Plugs OEM PZK14F For F150 F250 5.4L Pack of 8
The Motorcraft SP546 (also known as SP-546 or PZK14F) is a high-quality platinum spark plug engineered for optimal performance in various Ford and Lincoln vehicles. It serves as an updated replacement for the SP515, addressing earlier design concerns and enhancing reliability.
Product Specifications
- Part Number: SP546 / PZK14F
- Thread Size: 16mm
- Hex Size: 9/16 inch (14mm)
- Gap: 0.045 inches (1.14 mm)
- Torque Spec: 30–38 Nm (22–28 ft-lbs)
- Design: One-piece construction to prevent electrode breakage
- Shell: Nickel-plated for corrosion resistance
- Insulator: Multi-rib design to prevent flashover
- Electrode: Nickel-alloy for extended service life
- Service Interval: Up to 60,000 miles under normal driving conditions
Vehicle Compatibility
The SP546 is compatible with a range of Ford and Lincoln models, particularly those equipped with 5.4L V8 and 6.8L V10 engines. Notable applications include:
- Ford F-150: 2004–2008 (5.4L V8)
- Ford F-250 / F-350 Super Duty: 2005–2006 (6.8L V10)
- Ford F-450 / F-550 Super Duty: 2009–2010 (6.8L V10)
- Ford Expedition: 2005–2008 (5.4L V8)
- Ford E-350: 2007 (6.8L V10)
- Lincoln Navigator: 2005–2008 (5.4L V8)
- Lincoln Mark LT: 2006–2008 (5.4L V8)
Note: For vehicles with black coil boots, the SP546 is the recommended spark plug. If your vehicle has brown coil boots, a different plug (such as SP509) may be required.
Cross-Reference Part Numbers
The Motorcraft SP546 is equivalent to several other spark plug models, including:
- Motorcraft: SP515, PZH14F, PZT14F
- Autolite: HT15
- Champion: 7989
These alternatives can be considered if the SP546 is unavailable, but it’s always recommended to use the OEM-specified part for optimal performance.
❓ FAQ
Q: Which specific vehicle models and engines is this spark plug compatible with?
A: The Motorcraft SP546 is primarily engineered for Ford and Lincoln vehicles equipped with 3-valve 5.4L V8 and 6.8L V10 engines. This includes popular applications such as the 2004–2008 Ford F-150 (5.4L), 2005–2008 Ford Expedition/Lincoln Navigator (5.4L), and 2005–2010 Ford Super Duty trucks (6.8L V10).
Q: What older part number does the SP546 replace, and what design issue does it fix?
A: The SP546 serves as the updated factory replacement for the older, problematic SP515 (PZT14F) spark plug. It features an improved one-piece shell construction specifically designed to prevent the electrode shield from separating and breaking off inside the cylinder head during removal—a notoriously common issue with the earlier two-piece designs.
Q: What are the exact torque specs, gap measurements, and tool sizes needed for installation?
A: The SP546 requires a 9/16-inch (14mm) hex socket for installation, features a 16mm thread size, and comes with a pre-set gap of 0.045 inches (1.14 mm). When installing, it is critical to torque the plugs to the official specification of 22–28 ft-lbs (30–38 Nm) to prevent them from backing out or stripping.