ugh on that 3000 miles.
my dad used to go 6k between changes. i moved that to 10k. never noticed any problem with the car.
my ex uses synthetic & goes 20k
my family was insane about car DIY.
decades ago, a shop had left the oil plug off my uncle's car, messing him up badly. after that, my dad said all the car work was to be done at home.
i even had to change a timing belt once.
for 'safety' we drove half of it onto the curb, chocked with a rock 😂