what make is your car !

'Make' would sound more natural, as you are asking about the manufacturer - Ford, Toyota etc. 'Brand' is more of a marketing concept.

In the US, we use "make" only for cars and rarely for other mechanical objects.. The (trademarked) name for any other product is "brand". "What brand of shoes did you buy?" What brand of clothes do you prefer?" You will occasionally hear, "What make of dishwasher is that?" "Brand" can be used for cars but it's less common. Typically, though, we would ask, "who makes those shoes?" "Nike". ""What kind of car is that?" " a Ford" or "a Ford Focus."