2014 Silverado misfire no code?

[Ricky Rick]

I got 2014 Silverado with 5.3. Just changed my spark plugs because of a weird misfire under low rpm. Doesn’t do it if you get on it. Changed plugs and wires and was way over due. 150,000. One plug was a little wet and others were dry and all had carbon build up to the point not much gap anymore. Still does the same thing. Not throwing a code. Does it pretty bad at around 30 mph kinda like its dropping for 8 to 4 cylinders but misfire??  Any ideas?