1995 Oldsmobile Cutlass Brake system wear

When I changed rotor and pads last summer the new parts were hard to get into the wheels and they began to make rubbing moises right away everytime I backed up. Now 8 months later they make the same noises when driving forward. The brakes work fairly well and don't always make the scrapping noise but backing up always causes this problem.
What part of the adjuster system should I replace to keep the adjusters from eating the pads and rotors so early?