When I got the TM's for the M135 we could see rubber and steel lines laying in cradle channels above the diffs. The channels hold dirt so the lines can rot out quick. We just plan on replacing every piece of a brake system unless it's been done within the last year. It's the only way I know it's been tested and we have documentation.
Tires, steering and brakes are three things that get put in every budget before it touches the road. Even then it's only due dilligence. Things can still go wrong but in the pit of my belly, if I do everything I can to prevent an incident that still happens, I'm good.