2005 5.4 3V with Bad Cam Follower (2nd incident)
In August 2010, my truck started misfiring and making a bad knock from the passenger side of the engine. The dealer wouldn't even really troubleshoot and wanted to swap the engine. I took it for another opinion at a highly regarded independent shop and they pulled the valve cover and saw that it was a bad roller on the cam follower and it had worn a groove in the cam lobe. They replaced both the follower and the cam and it ran like new. Last week, a tick developed on the passenger side again and started misfiring so I took it back to the same shop. They pulled the valve cover again and this time, a different follower had gone bad and put a groove in the lobe. I'm having them replace both again. Since it's really not that much more money in the grand scheme of things, I'm having all of the followers replaced on that side. My question is what could be causing this? The mechanic said that the engine overall is in great shape. I'm pretty **** about changing the oil every 5k miles and run only Mobil 1 EP 5w20.
There have been no problems with the drivers side at all. Any ideas on the cause?