Originally Posted by elkaku

I just took apart the plastic part from the coil and used as a remover, once i got them loose and as a starter when putting them back in.... no hassle...😎😋

Originally Posted by Brian Jones

I just changed my spark plugs in my 2015 GK. The tools needed included the following: a 10mm and 14mm (thin walled, deep) socket. Two 3" extensions and possibly a universal joint. 10" ratchet and torque wrench. 12" section of fuel line. Plug gap checking tool. Pliers.
Getting the best plugs. I bought a set of plugs from a national chain auto parts store for about $9 ea. They were Iridium, but they weren't OEM. I checked them when I got home, and they were different from the OEM plugs (NGK 90137 DILZKAR7C11S Laser Iridium Plug). They were 1/8" shorter and had the iridium nib only on the center electrode, not on the ground electrode. The OEM plug has it on both. I decided I wanted the OEM, so I ordered the 90137 plugs from a major online autoparts vendor for $11.50 each; some places were charging $19 each, so shop around.
The plugs came gapped at .044". I closed up the gap to .041", halfway between the specified range of .039" and .043". I found that the old plugs had worn to an opening of .045". They were all worn and colored nearly the same. Nice. Not bad for 95,000 miles!
The process of changing the plugs was straight forward. Remove the rubber hose close to the left-most plug. Use pliers to release the clamp. Remove 10mm bolt holding ignition coil and pull its connector off (squeeze the back edge of the connector to release the tab). Pull the coil assembly up and out. Put the 3" extension on the 14mm socket and drop it in the plug hole (gently). It will go all the way in. Put the second 3" extension on the first and loosen the plug until it's turning freely. Take the ratchet off the extensions, and unthread the plug with your fingers. Pull the socket and extensions out. (On two of the plugs, you will have to pull off the upper 3" extension in order to pull the socket out. The plastic shield above the plugs gets in the way. This is why two 3" extensions work better than a 6" extension.) Put the piece of fuel line down in the plug hole and feel around until you can get it to slip over the top of the plug, and then pull the plug out. Gap the new plug to .041"--gently, the tiny iridium electrodes are a bit fragile and can break. Put the gas line on the new plug, and lower it in. NOTE: NGK plugs have an alloy coating that resists seizing; using an anti-seize grease will result in over tightening the plugs and possible thread damage (see link at GolNat's post below). Install the plugs dry. Thread the plug in by hand as far as you can. Finish tightening it with a torque wrench to 16 ft. lbs. Put the coil pack back on and tighten the 10mm bolt in place. Done with one; do the rest. Remember to put the rubber hose near the left-most plug back on.
Here's the picture fo the tools I used. The torque wrench isn't in the picture, but you need it to do the job well.