Which bushings wear out the fastest and need to be changed most often? Will changing bushings make the car quieter?

 

in most cases, no, bushings will not make the car quieter (unless they are completely shot). In reality, bushings don't need to be changed at all until really high miles. Most people who change them do so for the sake of improved handling/related improvements, due to the stiffness of aftermarket poly bushings vs. the stock rubber ones.