I have a 2015 Forester 2.5 6 speed manual. I have 140,000 miles and was wondering when I should change the belt, timing chain, and fluids? I have done oil changes, break pads, tires, 02 sensor, air filter, cabin filter, and rear wheel bearings. All else is stock. Also wondering if rotors ever go bad? I do the break pads myself. A few mechanics have said to not change break fluid, trans fluid, or anti freeze. I am mostly concerned about the belt and timing chain.