I took on the challenge of replacing my spark plugs this week; specifically the dreaded #8 plug.
Vehicle: 2017 Silverado with 5.3-liter engine.
If you are a seasoned mechanic and/or with strong hands, there is no need to read further. I am neither. I am over 70 and deal with arthritis in my hands so I am somewhat limited in doing things I used to do 30 years ago.
So, here is what I did:
1. Remove tire.
2. Remove the tire/engine interface cowling. A lot of small screws but maybe 20 minutes of work.
3. Fight for all your worth for about an hour to get your hand in there to 'twist and pull' that boot of the #8 plug.....which I could not get to come off......or.....
4. To get better access to the #8, I also removed the heat shield over the exhaust manifold. It took all of 5 minutes to remove the three bolts. That little bit of extra space gained made a huge difference and the boot came off.
5. Note: I used the high-temperature anti-seize to put the heat shield bolts back in place.

Anyway, in all the posts and Utube videos, I never heard of anyone removing the heat shield and in that little space around the #8 plug......every little bit of space gained helps.

KCE

 

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( there is no popular name,,,yet ) Save yourself lots of sweat & tears. $5 pricey. Worth every penny.

 

I feel your pain on #8 (I am your age). I also had to replace the oil sending unit on mine (2007 Tahoe 5.3L).