My rule of thumb has been cars get female names, and trucks get male names. as for your el camino, they can be either or for they are the trans-genders of the automotive world when you think about it (not in a bad way way, I like the lines of a good el camino or dare I say ranchero type vehicle lol). unless you go with object names like the guys on that show roadkill made a car I think they called it the "Raunchero" or they had Datsun called the rotsun haha.

as for mine, I was kidding around with my buddy Phil one day and he asked what her name was and I came up with Super Sue. Pretty corny eh.

 

IMO it's pretty gay to name your car. That's just me. To each his own.