Spark plug fouled with ~20k miles?

[bamafan76]

2 weeks ago, in my 11 Silverado 4.8L, I stopped at a red light and the truck started running rough. Service Stabilitrak message and flashing CEL appeared. Never died, and lights cleared once I took off. When I got home, I hooked my scanner up and received the generic cylinder, misfire error. I started small and removed all the spark plugs, where cylinder 5’s looked fouled. According to the maintenance records, the previous owner change the wires and plugs at about 56k miles in 2018. I changed them all. Since then, no additional issues.
 

Should I be concerned with this one?

[Bleepster]

i had the same cylinder foul out on my 2011 5.3L.  i replaced all the plugs and put in the AFM delete into the OBDII port and no problem ever since.  this was 30K ago

 

do you have Active Fuel Management (AFM)?  not saying this is the cause of the fouling, just sharing my experience

[bamafan76]

2 hours ago, Bleepster said:

i had the same cylinder foul out on my 2011 5.3L.  i replaced all the plugs and put in the AFM delete into the OBDII port and no problem ever since.  this was 30K ago

 

do you have Active Fuel Management (AFM)?  not saying this is the cause of the fouling, just sharing my experience

The 4.8L doesn’t have AFM (thankfully).

[Bleepster]

good to know.  i wasnt sure.