There is a lot of keyboard mechanical comment here. I'll risk a practical comment .Not very entertaining but useful ,I hope.
1 Spark plugs are cheap and fast to replace.Instead of "inspect" why not replace?
2.The tubes are prone to oil leakage and cracking - excellent reason for replacement of all.
3.The spark plugs may corrode at 60k if they were not very carefully installed with a very modest amount of anti-sieze (or leaking oil!)strategically placed. The cost of repairing a stripped spark plug thread ........... Related, do it yourself and chase+clean the threads in the cylinder head.
Hybrid Mode
