I have owned my 02 Tundra since October 2010. Since then, I have had both the passenger and drivers side calipers fail twice on me. First the passenger side in July 2011, then the drivers in December 2011, then the passenger side again in September 2012, and now my drivers side is not working again. When I had my passenger side replaced last they replaced the brake line saying that when they get old that sometimes pieces will come loose inside and act like a check valve and not let the fluid back out. I need to have the work done on my drivers side still but if what they told me the first time was true then I would like them to do the same thing to the drivers side this time. I know there have been problems with undersized calipers on my model but it seems like they cause rotor warping not caliper failures, but I am unsure whether I have the original or updated calipers at the current moment. Any suggestions as to why my calipers keep crapping out every 14 months or so? I had them completely bleed the brake system last time I had it in too in case the fluid was contaminated but I haven't had issues with the rear brakes outside of putting on new shoes, having the drums turned, and replacing the bell crank in December 2011 to pass safety inspections in my new state of residence.