does any one know how how to fix this problem when i start up my car and start to drive the brakes are ok but after driving for about and hour or so the brakes don't hold and the pedal goes all the way to the floor and i have to use the hand breake to slow down or stop i thought it was the pads but i checked the drums some time last week and they just needed adjusting but that that really did not help it just made the hand brake tighter and the front brakes are in good condition. i really need an answer ASAP please.

 

Not sure if this is your problem or not but brake fluid is made to absorb moister and over time can get water in it from condensation. Brake fluid can reach 300+ and water turns in to steam at these temps and steam is compressible and can cause mushy brakes. Your brake fluid is suppose to be flushed every few years because of this so if your brake fluid is really old I would try flushing it.

 

Try bleeding the brake system with some new fluid, DOT3 or DOT4 should be good. The new fluid should get all of the water and air out of the brake system.