[tall terry]

I don't worry about the hydraulic units failing. the lifter rollers are the real culprits... ask any one who has had one fail,,, these are a single tick,,, somewhat like a single lifter is bled down,,, a real engine slayer... an experienced w
ear is a must to diagnose one,, or a removal of the cams and lifters to do a visual...
these engines make some noises some are no real worries,,, others are the end of the engine