ok so i've got a 97 f150 with the 5.4 triton, first year for the motor, and we are the only owners of the truck, anyways this trucks seems to have an issue with the rear drum brakes not working right, and i don't think they are working cuz i have to tighten them twice a year and replace the front brake pads and sometimes a rotor, cuz they are taking all the pressure the back isn't. So my real question is, is there a valve or something that isn't working on the ruck making the rear drums not working or is this just a everyday thing for these trucks

 

Do the brake shoes show any wear? The only problems I have with my drum brakes is that they lock up a little bit when it rains. Do drums have brake hoses like the rotors in the front?

 

They have one soft line, but its usually in tbe center of the diff, and has two hard lines going out to each wheel.

Op, sounds like your adjustment wheel needs cleaning/replacing. Its an auto adjust system that does so when backing up usually.

 

did you try spraying on wd40 on the springs in the center of the drum assembly?

 

It is possible to have a bad master cylinder or bad proportioning valve. Usually it is the valve, since this gives the correct amount of fluid to the cylinders and calipers. Make sure that your power booster is working correctly.

You say you have to adjust them twice a year. That tends to lead a person to believe that the rears are working. Maybe not putting full pressure to the rears, but still working. I'd jack it up and have someone hold the brake and check if they are holding. If so, then the master is most likely working correctly. A bad module for the antiloc could also give you fits, but does not fit your description. I'd say it's in the valve or power brake booster.