The other day my breaks started acting up I can press the pedal one time and their fine let of and press again and it goes to the floor. It seems to be the worst when pulling up to a stop sign or something at slow speeds. I still have breaks but just enough to stop. A few people say its the master cylinder but just wanted to get some more opinions. THANKS>

 

if truck is more than two years old ,then you need to flush out all the old brake fluid,it,s losing it,s viscosity