So this one is interesting. My friend's family has a Hyundai Accent with fairly low miles, under 100K, that the father always took to Jiffy Lube for oil changes every 3K miles on the dot. Son mostly drove it, didn't warm it up ever, etc, or likely check oil. But the father was always on the dot with 3K oil changes at Jiffy Lube. I noticed about 2-3 years back at least the car developed a tick and then a knocking noise at startup, of which both the father and son ignored. I suggested perhaps switching to synthetic and seeing if it went away, and checking the timing chain, but I was ignored. To me the knock sounded like a timing chain slap or similar. I didn't notice any big drops/puddles on the ground at their place so it likely wasn't leaking oil, though.
Anyway, a couple weeks ago the son was driving it around in limp mode at 25mph and the mother finally took it in, and blown engine. So the timing chain didn't snap, as it still drove, but admittedly I don't know the actual failure point that occurred. Thankfully Hyundai is replacing the engine under warranty and did ask Jiffy Lube to fax over the oil change history.
This was one of the first Hyundai GDI engines, and I've heard of failures but this is a bit odd to me. Under 100K miles, oil changed often, etc. My father has the 2.4 in his Kia Sportage and it's had 180K miles and sounds great, but we've been mostly good with synthetic oil changes every 5K or so. No picture, but when the valve cover was pulled his mechanic said it looked brand new inside, timing chain still had a lot of tension and wasn't stretched, too. He also has a habit of warming up his cars in the morning, too, for about 2-3 minutes before driving away.
Maybe a bit controversial, but what do you guys think? I'll try to update if they can get me a specific thing like a rod being thrown in cylinder X, or bent valves, etc. But it's a surprising failure and makes me extremely unconfident in bulk conventional oil now, especially in a modern GDI car.