Spongy brakes

• If the brakes in your 1990 Jeep Cherokee feel spongy instead of rigid, there is air in the line. It takes two people to bleed the system. The bleeder screw is located right next to the hard brake line in the backing plate. Unscrew it a couple turns, have someone slowly depress the brake pedal to the floor, then tighten the bleeder again. Do that on all four wheels until there is no more air in the lines. Remember to watch the fluid level and catch the spent fluid in a proper container.
  
  

Pedal goes to floor

• If you have a large amount of play in the brake pedal of your 1990 Jeep Cherokee, it is very likely the pads and shoes need changing. As they wear, the brakes themselves have farther to travel to contact the drum or rotor. If you do not know how to change the pads and shoes, have a qualified technician help.
  
  

Loud grinding

• If you hear grinding noises when you hit the brakes, it's likely that they have worn down completely and are marring the rotors and drums of your 1990 Jeep Cherokee. Replace the pads and shoes immediately. In some cases, if the damage is slight, a shop can fix the rotors and drums by removing any harmful grooves. If the damage is bad, however, replacement will be necessary.