6.8L V10 tapping noise.

[Offramp]

My 2009 Class C motorhome is built on a 2008 E450 cutaway chassis with 51,000 miles on it. The engine is the 6.8L V-10 with 2 valves per cylinder. There is a tapping noise coming from the passenger side cylinder head. What kind of valve train issues are most likely the reason for this tapping. COPs, fuel injectors seems to be fine, Spark plugs changed at 51K and were in pretty good condition. The tapping seems to be near the valves for #1 & 2 cylinders.
Thank you.

 

[19Walt93]

If it's had reasonable maintenance valve train problems are rare. Warped exhaust manifolds and broken manifold studs were fairly common and the exhaust leak could make a ticking noise.

 

[Offramp]

Problem has been identified. A failing cam follower on #2 cylinder (roller bearing failure).
New Camshaft and 10 new cam followers to be installed on the passenger side cylinder head next week.