Newbie here. This is more of an info post, but if there are any thoughts, please send them to me.

I am the original owner of a locally purchased Chevrolet 2500 HD, 6.0L engine with 34,400 miles. Travel has been about 70 % highway and 30 % local. Towing a 6,000 lb trailer has been about 2,500 miles of that total. I have had routine service at recommended intervals, about 7,000 mile intervals, and have used whatever oil the Chevrolet dealer puts in the truck. Recently, after an oil change, the technician observed that there were metal particles on the oil drain plug and said they came from excessive wear of the rocker arms. Eventually, GM was willing to replace the rocker arms even though the vehicle was out of warranty. I did have to pay a portion of the repair.

When I talked to the service manager he had no suggestions for me to alter my driving habits, etc.

Any thoughts?
Thanks

I think that is B.S. Those rocker arms are roller tip and use less friction than older style rocker arms. If it wore that bad, the tips would have broken off and the engine would have run like crap. If it were metal particles, the first place it would have come from is the main bearings. IMO!

I know next to nothing about engines--just the theory of how they run!!

GM authorized a tear-down and the area was inspected. The invoice reads: "#1 exhaust rocker arm came apart. Replaced both banks all rocker arms. Removed and cleaned remaining needle bearings from oil pan. Refilled oil." Parts list includes 4 gaskets and 16 rocker arms plus the oil.

I did not notice any problem with the engine before the repair. It seemed to run well. I am just crossing my fingers and hope that nothing else is a problem with the truck. I sort of like it and want to keep it for a while.

Well I hope so friend. The only thing I can think of is if the roller tip bearing locked up and would cause it the break like that. But that is unusual to hear. If one rocker arm broke, depending on what, intake or exhaust, the motor would run like either a miss or backfire a lot. But hope this fixed it.