What Size Socket Do I Need For Spark Plugs? [An Ultimate Guide]

A spark plug socket is important in extracting and installing spark plugs, one of the essential auto repairs.

Spark plugs usually last 30,000 miles before needing replacement, although this varies depending on how much your engine runs.

Because they are positioned deep inside an engine’s block, the only way to remove them is by using a socket wrench fitted with the appropriate spark plug socket size.

Spark plugs typically need a 5/8″ (16mm) socket, which relates to the size of the flats on the spark plug that touch the socket.

Learn everything you need to know about Spark Plug Sockets in this article.

What is a Spark Plug Socket?


A spark plug socket features a foam rubber insert that sits within it to help keep the spark plug in place while preventing it from being damaged by its interior walls.

Hence, these sockets are longer than conventional sockets to support the spark plug’s tip. They have a wider clearance depth and opening depth.

What is a Spark Plug Socket For?

Spark plug sockets are used for the installation or extraction of spark plugs. Though the spark plugs on certain engines are found deep within, you may need to extend the spark plug socket to access them.

Two Types of Spark Plug Socket

There are two primary sockets you may pick from, and they both function well. For most people, it’s more of a personal choice.

Socket with Magnet

This type of spark plug socket is magnetic, making it costly. However, these are more dependable and durable than rubber equivalents.

Socket with Rubber

Rubber grommets are used for this socket’s interior to keep the spark plug in place. Hence, these are cheaper.

Read More:  How To Load A Staple Gun [Manual, Electric, Or Pneumatic]

What Are The Common Sizes Of A Spark Plug Socket?

There are various spark plug socket sizes available. Specifically, 14 mm (9/16”), 16mm ( 5/8″), 18mm, 19mm (3/4″), 20mm (13/16′), 21mm, and 7/8″ are the common sizes of these sockets.

It’s essential to make sure you’re using the right spark plug socket for your vehicle. Using the wrong size will likely damage the spark plug and make it hard to remove.

Spark Plug Socket Chart

It’s unusual for an engine manufacturer to use the same spark plug size throughout its models. Here is a spark plug socket chart for your convenience.

However, the chart only lists some of the most prevalent applications. To get the most precise results, perform a Google search for the year, manufacturer, and kind of engine you have.

Steps on using Spark Plug Socket for Auto Repairs

Step 1: Locate Spark Plugs in Opened Hood


First, open the hood of your automobile, then look for the distributor cap. It is a circular cap with multiple thick wires inserted into the top. Follow these wires to the engine block. Each connects to a separate spark plug.

Step 2: Unplug Wires from Spark Plugs

One by one, remove the wires. However, they might hold on tightly, so pull firmly until free. If you don’t want to get confused about which cable goes where do one at a time.

Step 3: Choose the Correct Spark Plug Socket Size

Pick a socket that appears to fit with the spark plug’s tip. Place it over the tip while carrying it in your hand. Adjust the socket’s size if necessary. The proper socket should securely fit the spark plug’s tip and not revolve around it.

Step 4: Connect Spark Plug Socket to Wrench

A smaller square hole is located on the reverse of the socket. This is where the driver goes. Drivers come in various sizes, so choose the one that best matches your needs.

Read More:  Corded & Cordless Hammer Drills [5 Best For Concrete]

Attach an extension between it and the socket if you need to reach deeper. Assemble the parts by snapping them together.

Step 5: Disconnect the Spark Plug by Loosening it

Surround the plug with the socket. Then spin counterclockwise (to the left). Rotate until you can feel that it’s loose. Remove the plug by reaching inside.

Step 6: Change and Clean the Spark Plug


The metal hook-like end of a faulty plug will be coated in blackened soot. You might be able to wipe it off with an emery board or fine sandpaper, but it should be replaced if the plug is old enough.

Ensure that the new plug is the correct size. Set the socket wrench to tighten, then lock it in position. Turn the wrench to the right, and the ratchet should be turned to the left.

Repeat these procedures for each of the remaining plugs. It’s better to replace all of them if they’re old.

Top 7 Best Spark Plug Socket

1. Gearwrench Magnetic Swivel Spark Plug Socket 

GEARWRENCH’s magnetic swivel spark plug socket is intended to make replacing your spark plugs as simple as possible.

This 6′′ 5/8′′ spark plug socket has a 3/8′′ drive and comes with a fully-featured extension and universal joint for 360-degree swivel operation. A knurled grip on the tool’s shaft aids in providing a non-slip surface for low-torque applications.

Moreover, this famous spark plug socket has a magnet, much like the other products on our list, which helps hold and secure the spark plug for simpler installation.

Furthermore, unlike a standard rubber gasket used in other spark plug sockets, it doesn’t wear out over time.

2. ARES 5-Piece High Visibility Spark Plug Socket Set

Are you unsure about the size of your whip’s spark plugs, or do you work on a range of vehicles? Getting a five-piece set is essential.

Read More:  How to Remove a Torx (Star) Security Screw Without a Screwdriver? [Simple Ways]

There are a handful of metric sockets on this set, as well as three Freedom sockets. The dimensions are engraved and pounded into the walls.

This spark plug socket set comes with sizes 5/8-inch, 3/4-inch, 13/16-inch, 14mm, and 18mm, as well as a storage rail.

The rubber retention ring keeps plugs in place, and the tapered 6-point socket ends grab the flat sides of the fastener head rather than the corners, preventing rounding.

3. Powerbuilt Spark Plug Socket Set

If you work on various engines, you’ll need a set of spark plug sockets in several sizes. This set includes 5/8′′, 3/4′′, 13/16′′, 14mm, and 18mm.

These chrome vanadium 6-point deep spark plug sockets include a thin wall, mirror-polished finish, and twin grease rings. A rubber retaining ring is located inside each socket to keep the spark plug in place.

In addition, they meet or exceed ANSI standards and are backed by a lifetime warranty.

4. Craftsman Spark Plug Socket Set

This is a simple spark plug socket, which is required in some situations. What makes it even better is that there’s no need for extensions or swivels with this product.

After all, most of you probably have quite enough extensions in the garage without acquiring more with an all-in-one set.

5. LEXIVON Swivel Magnetic Spark Plug Socket

This 5/8-inch spark plug socket has a total reach of 10 inches. With a smooth 360-degree ball swivel, you should be capable of reaching into even the most cramped engines.

It includes a mirror finish that is thoroughly polished and chrome-plated to prevent rusting.

Although it does not run the length of the socket, a knurled shaft resists slippage, and its size is laser carved onto the socket.

6. Apex Tool Group GearWrench Tools Magnetic Spark Plug Service Kit

If you work on a range of engines and know you’ll need a 5/8″ spark plug socket, check out Apex Tool Group’s spark plug servicing kit. This extended reach swivel spark plug set comes with magnetic cores in 4′′, 6′′, and 11′′ lengths.

Read More:  Bosch 18v vs Dewalt 20v Cordless Drill Driver [Before Deciding]

The 5/8′′ spark plug socket comes in three lengths, allowing you to tackle a variety of circumstances with ease. On the other hand, the 6′′ and 11′′ tools have knurled shafts for greater gripping if needed.

In fact, Apex Tool Group offers a lifetime guarantee on this package, including a convenient blow mold box for storage.

7. Neiko Magnetic Spark Plug Socket

Neiko offers a 5/8′′ magnetic spark plug socket with an 11-inch extension, 360-degree swivel, and 3/8′′ drive.

This spark plug socket is identical to many others on our list. However, its 11′′ extension is a little longer than others. It is made of chrome vanadium steel for longevity and durability.

Furthermore, The shaft has a sculpted knurled grip for ergonomic comfort and a non-slip surface. It has a completely refined, chrome-plated mirror finish to prevent corrosion and rust.


Do You Need Colder Spark Plugs?

According to this post, this is a common question and it, unfortunately, gets answered incorrectly most of the time or incites a flame war. Spark plugs in general are always a controversial topic – copper vs iridium, hotter vs colder, single or multiple electrodes, brand vs brand, and plenty more.

Is Using a Spark Plug Socket Needed?

To remove and install spark plugs, you don’t need a spark plug socket. In most circumstances, a deep socket of the proper size and perhaps some pliers to go with the socket would suffice.

What Can You Do Without The Right Socket?

YouTube video

In this video, a mechanic will demonstrate a spark plug hack if you don’t have the right-sized socket.

First, you’ll need to roll a sheet of aluminum and then put it in the socket. You’ll need to use a screwdriver to round the edges for a funnel effect. With this, you’ll be able to extract or install spark plugs.

Read More:  What Is A Spud Wrench Used For In Plumbing [The History]

It will take a couple of times, but it is the easiest fix for your issue when you currently can’t access the store to buy a proper socket.

Keep this in mind. This shouldn’t be an alternative but only a last resort. To ensure the procedure is smooth, ensure the proper size socket for future applications.

When Should Spark Plugs Be Removed?

Spark plugs are durable components and don’t need to be replaced too often. However, the general recommendation is about every 30,000 to 90,000 miles. Each vehicle may differ on when it should be replaced.

Can You Clean A Spark Plug With WD-40?

WD-40 removes carbon residue and keeps moisture away from spark plugs and wires. WD stands for Water Displacement, so if your spark plugs are wet or you need to drive moisture away from ignition distributors, this will do the trick.


Without a spark plug, gasoline will not ignite. So, every time you have a technical problem with the engine, it is the first item you should inspect.

Problems arise at unpredictable times, and you may find yourself in a scenario where you lack the necessary equipment. With this article, you can learn how to use the tools you have to remove a spark plug.

Leave a Comment