I've got a 2005 Pathfinder with about 150k on the odometer. It's been an incredibly reliable and robust vehicle. There have been maintenance items like various sensors, but nothing outrageous. I replaced the radiator with a CSF unit as a precautionary measure, and rebuilt the chassis and suspension a couple of years ago before a trip up to Tuktoyaktuk. Recently I started noticing a bit of a whine in the engine at idle. I can't hear it when I'm in the truck driving, but I notice it in a drive through or when I'm parking in a garage with the window down. Originally I thought it was the alternator, but that was wishful thinking. I'm pretty sure it's the timing chain whine.
So my question for some of the more experienced members on the board, is how far do I go when replacing the timing chains and tensioners? It's a massive job, and I'm comfortable tackling it because I can take my time. In doing all that work though, is it worth taking care of other items while the front of the engine is torn down? The water pump is pretty obvious, but what about replacing the starter motor while it's out of there, or the power steering pump? It feels like in this case the cost of extra parts is relatively manageable compared to the time involved in actually doing the job. Am I being overly conservative? Where should I draw the line?