What Size Of Spark Plug Socket Does This Take? A 3/8's Or A 5/8's?

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BOSCH 4417 FGR7DQP Platinum+4 spark plug - Single

Q: What size of spark plug socket does this take? a 3/8's or a 5/8's?

asked on September 9, 2013

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I know this is an old question, but some clarity is needed here. 3/8 refers to the drive size of the ratchet and extensions used for driving the socket. Most people use 3/8 for servicing spark plugs, so most spark plug sockets are 3/8 drive. There are 1/2 drive spark plug sockets, but it is unlikely that is an issue. I… see more I know this is an old question, but some clarity is needed here. 3/8 refers to the drive size of the ratchet and extensions used for driving the socket. Most people use 3/8 for servicing spark plugs, so most spark plug sockets are 3/8 drive. There are 1/2 drive spark plug sockets, but it is unlikely that is an issue. I have never heard of a 3/8 size spark plug. Most spark plugs require a 5/8" (16mm) size spark plug socket. This refers to the size of the flats on the spark plug that are in contact with the socket. This spark plug requires the 5/8" spark plug socket, which will probably fit a 3/8 ratchet extension. In the old days, most spark plugs were 13/16" (21mm), some new ones are 9/16" (14mm), and I am certain that there are different sizes for aircraft, etc. But there is no such thing as a 3/8 spark plug. For most folks a 3/8 drive 5/8" spark plug socket is the way to go for this spark plug. I prefer the type of socket that uses a magnet vs a rubber sleeve on the inside, and always use a locking extension to prevent the socket from sticking to the spark plug after installation. see less I know this is an old question, but some clarity is needed here. 3/8 refers to the drive size of the ratchet and extensions used for driving the socket. Most people use 3/8 for servicing spark plugs, so most spark plug sockets are 3/8 drive. There are 1/2 drive spark plug sockets, but it is unlikely that is an issue. I have never heard of a 3/8 size spark plug. Most spark plugs require a 5/8" (16mm) size spark plug socket. This refers to the size of the flats on the spark plug that are in contact with the socket. This spark plug requires the 5/8" spark plug socket, which will probably fit a 3/8 ratchet extension. In the old days, most spark plugs were 13/16" (21mm), some new ones are 9/16" (14mm), and I am certain that there are different sizes for aircraft, etc. But there is no such thing as a 3/8 spark plug. For most folks a 3/8 drive 5/8" spark plug socket is the way to go for this spark plug. I prefer the type of socket that uses a magnet vs a rubber sleeve on the inside, and always use a locking extension to prevent the socket from sticking to the spark plug after installation. Present · January 6, 2014 9 people found this helpful. Do you? Yes | Report Most spark plugs require a 5/8" (16mm) size spark plug socket. This refers to the size of the flats on the spark plug that are in contact with the socket. luis · July 12, 2021 4 people found this helpful. Do you? Yes | Report 5/8 HHNYC · September 9, 2013 Do you find this helpful? | Report 5/8" !! NOT 3/8" as in another answer. Clay · September 16, 2015 Do you find this helpful? | Report 5/8's G. Johnson · September 12, 2013 Do you find this helpful? | Report I believe 5/8" is the standard size for nearly all spark plugs I have come across, automotive as well as lawn and garden. Only the length varies. AJ Tissier · September 10, 2013 Do you find this helpful? | Report 9/16 or 14mm socket Karla rodriguez · July 23, 2021 One person found this helpful. Do you? | Report 14mm. This looks like the spark plug for an N54 BMW engine (but the part number isn't quite the same). For those not only do you need a 14mm spark plug, it needs to be thin-walled and you need to have an angled adapter or it needs to have a built-in angled extension because the walls forming the "tube" the spark plug h… see more 14mm. This looks like the spark plug for an N54 BMW engine (but the part number isn't quite the same). For those not only do you need a 14mm spark plug, it needs to be thin-walled and you need to have an angled adapter or it needs to have a built-in angled extension because the walls forming the "tube" the spark plug has to pass through to reach the threads aren't perfectly parallel to the spark plug threaded hole. This means that once you start driving or removing the spark plug, the socket will collide with the wall and your socket can either get very stuck or worse, you could break the spark plug off, part of which may drop into the combustion chamber and really ruin your year. Lastly, in order to torque the spark plugs properly to spec, you need to factor in torque angle because there is no way to torque them in straight. see less 14mm. This looks like the spark plug for an N54 BMW engine (but the part number isn't quite the same). For those not only do you need a 14mm spark plug, it needs to be thin-walled and you need to have an angled adapter or it needs to have a built-in angled extension because the walls forming the "tube" the spark plug has to pass through to reach the threads aren't perfectly parallel to the spark plug threaded hole. This means that once you start driving or removing the spark plug, the socket will collide with the wall and your socket can either get very stuck or worse, you could break the spark plug off, part of which may drop into the combustion chamber and really ruin your year. Lastly, in order to torque the spark plugs properly to spec, you need to factor in torque angle because there is no way to torque them in straight. Nick D. · September 19, 2021 Do you find this helpful? | Report i used a 3/8" spark plug socket for these plugs imoorad · September 9, 2013 One person found this helpful. Do you? | Report Sorry, I don't know. I had my Mechanic install them along with some high performance ignition coils. DML · September 9, 2013 Do you find this helpful? | Report

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