I think it's a fandom-wide headcanon that Sheriff is stubborn about his health (he never wants to admit he's sick, etc) but what do you think about Lightning? Do you think he's stubborn too, or would he just willingly comply with every health-related thing Doc asks of him because he knows that he can't get out of it?
I think Lightning’s probably pretty pro-maintenance! Because he likes being pretty, lol, and he likes peak performance, and he likes feeling like everything’s doing what it’s supposed to and is going to continue doing that. XD I’ll bet that if cars can get colds, Lightning’s the kind of guy who’s just like “Oh is there medication for this? Cool, I’ll take seven. I’M NOT JUST GONNA STOICLY SUFFER THROUGH THIS. GIVE ME–! THE AMELIORANTS–! >:O”
Plus I feel like he’s probably really used to his existence being closely managed, if that’s the right word. There’s pre-race inspections and post-race inspections and over the course of any given single race he probably goes through more maintenance than a street car would in their first five years of life–to say nothing of all the testing and adjustments in the week leading up to a race. And then after the race, it’d be a given standard of his life that he’d get parts replaced every week that most cars will never have to replace in their entire lifetimes!
While all that probably isn’t the most pleasant, it’s his normal; and it probably didn’t occur to him for a long time that a non-racecar would find any of that strange. XD
I think where Lightning gets less accepting of care is when he doesn’t want others to worry about him, or when he doesn’t really see how something could be fixed–like, when there isn’t something that will just automatically and certainly address whatever issue he’s having (e.g. assuring Sally that he’s fine right before the Florida 500).