October 2011 I had the serpentine belt & tensioner replaced. Febuary 2013 (this week)- i took my car in b/c it was making wicked sounds. I was toldi needed a pump-power steering $130, Line-power sterring pressure- $170 an $113 for a tensioner-belt- total came to $754. I pulled out my invoice from October and was surprised that the tensioner-belt from 2011 and charged $130. for would already need to be replaced. How long do they last? Or did I get ripped off?