Originally Posted by
mtbikerinpa
I have been using Deore Hydros for almost a decade now with no problems winter/rain/mud/etc. Everyday use regardless of weather, only an occasional centering adjustment. I've had more problems with my car's brakes by a long shot. One change I made however was when I rebuilt them for the sake of it after 5 years of racing, I used ATF/Hydraulic oil instead of shimano brake fluid(upon recommendation of a reputable mechanic) and it apparently hasn't been a problem, perhaps a help?
The mechanical ones on the other hand have had far more maintenance requirements in my experience. That goes for Avid BB5 BB7 and Formula mechanics. To each their own, but the hydraulic mechanism is sealed much better. For cost reasons my lesser commuter bike has BB5s and yes they work, but would I want them in continual wet/frozen... not as much.
I don't know why my Deores gave me so much headaches, maybe it was defective from the factory or maybe just bad luck on my part. But after having seals replaced twice I just gave up and changed to cable discs. I still have those brakes in my parts bin, maybe some day I'll rebuild them one more time and try ATF fluid instead of that super expensive shimano oil.