Hey guys, well, lets start with my predicament. I have a derailleur that is 3 years old, its a Shimano XT and it seems to be ghost shifting, or just not shifting at all. It shifts when i'm walking my bike...So i'm wondering, should i replace it with a SRAM X.9? or should i try to adjust it. And how often should a derailleur be replaced because i have no clue?