What size socket is for CX5 spark plug SKYACTIV ?

How To inspect / replace Mazda CX 5 2.0 litre (Skyactiv) Spark plugs :

Tools :
1. 8 mm socket
2. 14 mm Long socket (spark plug socket)
3. Wrench & extension

Step 1 :
Remove engine cover


Step 2 :
Locate 4x 8mm nuts holding on the ignition coils


Step 3 :
Access the spark plug by using the 14mm socket .


Done .

I couldn't find the size, but I found the tightening specs lol

SPARK PLUG REMOVAL/INSTALLATION [SKYACTIV-G 2.0]
CAUTION:
If a spark plug that is not as specified is installed, engine performance will be deteriorated.
Install only the specified spark plug when replacing.
1. Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE
DISCONNECTION/CONNECTION [SKYACTIV-G 2.0].)
2. Remove the plug hole plate. (See PLUG HOLE PLATE REMOVAL/INSTALLATION [SKYACTIV-G
2.0].)
3. Remove the ignition coils. (See IGNITION COIL/ION SENSOR REMOVAL/INSTALLATION
[SKYACTIV-G 2.0].)
4. Remove the spark plugs using a plug-wrench.
5. Install in the reverse order of removal.
Tightening torque
15—20 Nm {1.6—2.0 kgfm, 12—14 ftlbf}

In general there are only 2 standard socket sizes, 13/16 and 5/8. A true spark plug socket will have a little rubber gasket inside to prevent the plug from slipping out during removal/replacement. You could technically use any proper size deep well socket though.
So, try a 5/8, if it is too small then try a 13/16. I would say that if you don't own those two sizes then maybe changing your own plugs is not the best idea for you.

Do you have 60,000 miles yet. I'm all for changing plugs a little early. Car has only been out a little over a year. Be carefully of what plug you use.
http://parts.arlingtonmazda.com/products/PLUG,SPARK-DENSO-(PE02%2d18%2d110).html

25 bucks each US. They must be good.

Thread updated please move to HOW TO section .