Is this a common problem ? After talking to a parts guy, he said
it always seems to be the right rear that goes first. The sliding pin
rusts in the bore.

 

I too have had that problem, especially in the colder weather.

 

if the person who did your brake job didnt use anti seieze on the sliders then it could easily happen. personally i dont trust anyone else to do mine so i do them havent had any probles in the 8 years ive had it. alot of cars sliders do seize up. i see it all the time at my dads shop.