i jus got my 1983 rx7 and i hear a knocking noise coming from the rear right tire i looked and it looks like its missing the lower caliper bolt now its sound logical enough that thats obviously the problem but is it common and how do i go about fixing it....o yea and how do i kno its not the wheel bearing????

 

Does it sound all the time?

 

yea it makes alot of noise up until i get to about 40mph then it stops a little but i can also see where the caliper has slid about an inch off the break pad