On your truck gender, as you probably know, english doesn't really use gender's, but still, people 'can' use genders. I think more guys would refer to their truck as "it", or her/she.
However, ...not to confuse you, but if a male owner gave his truck a pet name, which a lot of owners do, more than likely it would be on the masculine side, like: Old Blue, The Gray Ghost, The Big Red Dog, Ole Red, The General, TRex, Night Stalker, ...even Rebel ...to me signifies masculine. A truck is supposed to be tough and strong. I can't imagine a guy calling his truck, Princess Of The Swamp! or The Sweet Lady ...LOL.
Now, if the truck was a lady-owned pickup she might give it a feminine name.
But if you're referring to something
about your truck guys will use 'it'. But a lot of guys will say 'her' also; "I'm going to give
it/her all new fluids." "I am going to buy a new bed cover for
it/her". "
She's/it's got a few dents." "It was a difficult trail but
she/it got me out of the woods in one piece."
I
never hear guys say, "I'm going to give
him new oil and fluids." or, "It's about time to buy
him new tires."
He's got a few dents. Personally I would avoid using He in those cases. That would be wierd for a guy to say that. But an owner might say, "I've got to change oil in 'old Blue' this weekend" (or whatever pet name an owner might have given his truck (if he had a pet name for it)).
These are generalities based on what I've heard over the years. Maybe there's an English teacher here who can shed more light on the specific 'Rules' ....