So for starters i blew the back driver caliper. replaced that and now i have intermittent loss of breaks. legit goes to the floor, i can pump them and they will work but they still keep doing it, now we have legit emptied refilled and nothing , replaced the master break cylinder and nothing. The breaks have been replaced all around over the course of the last two weeks , from one week back the following then less than 3 days later bam the caliper went. now I am not sure where to start i am not losing fluid i am not finding any leaks anywhere and here i sit... lost.. can someone point me in the proper direction of what i might try to heal my trucks ailments?

 

Gravity bleed the calipers at all four corners to get the air out of the system. Start where the back driver caliper blew.