What size socket for F150 spark plug?

The quick answer: most Ford F-150 spark plugs are removed with a 5/8-inch spark plug socket, but some engines may require a 13/16-inch socket. Always verify for your exact model year and engine code.

The Ford F-150 has evolved through many generations and engine options, from older V8 setups to modern EcoBoost and hybrid powertrains. Because the spark plug hex size can vary by engine family and year, using the correct socket is essential to avoid damage or a stuck plug. This guide covers the typical sizes and how to confirm the right one for your specific truck.

Common socket sizes for F-150 spark plugs

Before listing the sizes, note that the two most common spark plug socket hex sizes you’ll encounter on F-150 models are:

• 5/8 inch (approximately 16 mm) spark plug socket — the most common size for many F-150 engines.


• 13/16 inch (approximately 21 mm) spark plug socket — used on some engines or specific years when the plug hex is larger.

Having both sizes on hand helps you cover most F-150s across different model years without a return trip to the toolbox.

How to confirm the exact size for your truck

Use these steps to ensure you buy or use the correct tool for your particular F-150:

• Check the owner’s manual or the official Ford service manual for the spark plug specification and the recommended socket size for your engine.


• Identify your engine code or VIN and look up the spark plug size in Ford’s service information or trusted repair databases.


• Inspect the spark plug hex on a removed plug (or the plug packaging) to verify whether it matches 5/8" or 13/16"; the socket you need should fit snugly over the plug’s hex.


• If you’re unsure, bring the removed plug or a photo to an auto parts store and have them confirm the correct socket size for your engine family.

Using the correct socket size helps prevent slipping, stripping the plug, or dropping a tool into the engine bay during installation or removal.

Summary

In practice, the default spark plug socket size for many Ford F-150 engines is 5/8 inch, with 13/16 inch required for some engines or years. Verify your exact engine and model year through the manual or Ford’s service information, and consider keeping both sizes on hand if you work on multiple F-150s. A properly sized socket is a small, yet essential part of a safe and successful spark plug replacement.

What size socket for spark plugs Ford F-150?

The spark plug socket size for a Ford F-150 is typically 5/8 inch, but 9/16 inch is needed for certain engines, particularly the 5.4L 3-valve Triton from 2004-onward. It is important to confirm the specific size for your year and engine, but having a 5/8 inch and a 9/16 inch spark plug socket is a good starting point.
 
Common sizes

• 5/8 inch: The most common size, used on many newer F-150s, like the 3.5L V6 and 5.0L V8. 
• 9/16 inch: Required for certain engines, especially the 5.4L 3-valve Triton V8 from 2004 and later. 

Important considerations

• Spark plug socket vs. regular socket: Always use a dedicated spark plug socket. It has a rubber insert to hold the plug and a longer, thinner design to fit into the spark plug tube. 
• Confirm your engine: Double-check your specific F-150's year and engine to confirm the correct socket size before you begin. 
• Extension and ratchet: You will also need a 3/8-inch drive ratchet and an extension, with a 6 to 9-inch length being common. 

What size socket is a 2008 Ford 5.4 spark plug?

If it's an early 2008 model, you'll need a 9/16 plug wrench.

What size spark plug socket 3.5 ecoboost?

So they come pregapped. We're going to link all of these part numbers in the description. Below i did put just a tiny bit of copper hightemp anti-seas on the threads.

What size socket do I need to pull a spark plug?

The most common socket sizes for spark plugs are 5/8 inch (16mm) and 13/16 inch (20mm), but other sizes like 9/16 inch (14mm) and 3/4 inch (18mm) are also used depending on the vehicle. The exact size depends on the make, model, and age of your vehicle. You may need to check your vehicle's manual or measure the spark plug to find the correct size. 
Common spark plug socket sizes

• 5/8 inch (16mm): The most common size, used in many modern and small-engine vehicles, as well as motorcycles. 
• 13/16 inch (20mm): Often used in older and larger-engine vehicles. 
• 9/16 inch (14mm): Frequently found in Ford vehicles, newer European and Asian cars, and some motorcycles. 
• 3/4 inch (18mm): Used in some motorcycles, small engines, and older GM vehicles. 
• 11/16 inch (18mm): Used in some motorcycles, small engines, and older BMW vehicles. 

You can watch this video to learn about different socket sizes and how to use them: 1mDanny Johnson’s GarageYouTube · Aug 3, 2025
Tips for choosing the right socket

• Consult your vehicle's manual: This is the most reliable way to find the correct size. 
• Measure the spark plug: You can measure the hexagonal part of the spark plug to find its size. 
• Look for a "spark plug socket": These are specifically designed for spark plugs and often have a rubber insert to protect the porcelain insulator and hold the plug in place. 

This video demonstrates how to use spark plug sockets: 51sbeachtrollYouTube · Sep 7, 2018