Yep the noise is always there, when you start it at -20 it's faint until it warms a bit and it is very distinct in the cab too. It was very consistent, didn't matter the load or speed. Mine was quite loud, I'm surprised it didn't seem to damage the cam, the cam wasn't even off color.
I still don't have number three spark plug replaced
, that sucker is tighter than hell, it won't budge, tried it again the other day with the engine warm, then cold, then hot. I'm thinking of using one size smaller socket, lowering it over the porcelain then smacking it a few times with a hammer, then trying it. That's basically how I got the other one loose but I used an air hammer because I couldn't get in there. I think the person that installed the last set tightened them up too much. It requires only thirteen ft/lb.
I did another '07 5.4l the other day broke off four in that engine too, they rust in there, it has only a 125,000km on it. I installed one piece Champions in it but for some reason the sucker misss on #8 and #2 when cold now, it seems to run fine warm, I guess I'll pull them and double check the gap. I love these engines but this is a real PITA.