What size are Ford spark plugs?
Ford vehicles use a variety of spark plug sizes depending on the engine model and year. The most common spark plug sizes for Ford engines are 14mm and 18mm. In this article, we'll provide a detailed overview of the typical spark plug sizes found in Ford vehicles.
14mm Spark Plugs
Many Ford engines, including those found in the Ford Mustang, F-150, and Expedition, use 14mm spark plugs. The 14mm size is the most common spark plug diameter for Ford vehicles. These spark plugs have a thread diameter of 14mm and a reach (the length of the threaded portion) of around 19mm to 25mm, depending on the specific engine application.
18mm Spark Plugs
Larger Ford engines, such as those found in the Ford Super Duty trucks and some V8-powered models, often use 18mm spark plugs. The 18mm spark plugs have a larger thread diameter and are typically used in engines with higher compression ratios or larger displacement. The reach of 18mm Ford spark plugs is generally between 12mm and 19mm.
Identifying Spark Plug Size
- Check your owner's manual or service manual for the recommended spark plug size for your specific Ford model and engine.
- Inspect the existing spark plugs in your vehicle to determine the size.
- Look for the spark plug size stamped on the side of the plug itself.
- Measure the diameter of the spark plug threads using a caliper or spark plug socket.
Knowing the correct spark plug size for your Ford vehicle is important to ensure proper fit and performance. Using the wrong size spark plugs can lead to issues such as misfiring, poor fuel economy, and engine damage.
