Spark plug socket size

5/8" also known as 10/16". Yours is 3/16" too small.

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What size spark plug socket do I need? - Jeep Forum

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Dec 26, 2009 - 5/8" deep well spark plug socket.

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When you buy the new spark plugs, take one of the plugs and get a spark plug socket to fit. The size may depend on the brand? Try 5/8 spark plug socket. Hopefully the socket for the new plugs will fit the old plugs?

Take to your local auto parts store. They can look it up and give you the correct spark plugs you need & the gap spec

Open the hood & under it there is a Federal Emissions
Label on all vehicles with the spark plug gap

That label has been there for 40 years or on radiator support

8 mm according to my Pugeot and Mercedes reference.

I would have a complete set of 3/8" Metrics 12 pt sockets on hand to be sure at the time of doing the job as sometimes our manuals are not exact due to the many variables.

It shows a thin walled 12 point metric. I know my BMW uses a 10MM thin walled for the irridium plugs.

You can find the tool mentioned on eBay, it has a special clip to retain the plug as you extract & insert it.
Mercedes M156 engine, Peugeot 207 and 307, Renault 1.2 16v SPARK PLUG SOCKET 8MM Item #120884075060.

Good luck!

With the engine cool using the same tools you simply have to take your time and feel for the plugs very simple apply socket to remove and replace spark plugs in the back or follow the wires they're connected to pull feel remove piece of cake!!!

NORTHSTAR 4.6 ENGINE REMOVE INTAKE MANIFOLD SERVICE COVER FROM THE ENGINE.SPARK PLUGS IN THE VALVE COVER BUT THE SPARK PLUGS NOT HARD TO CHANGE.YOU NEED A LONGER SPARK PLUG SOCKET OR YOU USE REGULAR SIZE PLUG SOCKET USING LONGER EXTENSIONS.YOU NEED SPARK PLUG BOOT PULLER.YOU NEED A UNIVERSAL JOINT.BESURE TO GET PIECE RUBBER HOSE 10 INCHES OR WHAT EVER SIZE PLACE HOSE OVER SPARK PLUGS FOR THE HARD TO REACH SPOTS TO HELP AID SPARK PLUG BACK IN WITHOUT STRIPPING THE THREADS.HOPE THIS HELP.

if its your first time you need a haynes repair manual.you need a spark plug boot puller.you need 3/8 ratchet wrench.spark plug sockets.from size 5/8 to 13/16.you probably need size 5/8 socket.you need extensions different sizes.and universal joints.to reach hard to get plugs.you need torque wrench. and spark plug gap set.

The standard size of 5/8 spark plug socket with a 1/2 drive.

just go to a local parts store and they will give you all you need. spark plugs are not that difficult to size with the right parts salesman.