Lifter ticking

[Nessmuk]

Got in a mess last trip and my radiator overflowed onto my aur cleaner. I had to run without one to Tennessee and back.
I now have lifter noise. I figure I have dirt in it. I changed out my nice, expensive Mystik 15w50 for fresh. The noise is intermittent. Do you think it will go away?

 

[3500GMC]

Tough call, those plastic rocker arm locater buttons can fail and get noisy but that's usually associated with a broken pushrod and a miss/backfire

Any smoke or dropped cylinders?

 

[MrMarty51]

I hope it is nothing too serious.
Can You get a location where it is coming from, using a stethescope or a long screw driver held to the ear ?

 

[Nessmuk]

It's definitely a tinny, upper engine sound. It has issues, but it seems to hit on all eight.