Question: what is the first thing to do after buying a used car?
Answer: That intoxicating ' and possibly noxious ' new-car smell isn't the only thing differentiating new vehicles from 'second-hand cars. ... 
Change your motor oil. ... 
Flush your engine coolant. ... 
Replace your brake fluid. ... 
Swap your battery sooner. ... 
Look after those filters. ... 
Change your transmission fluid.