Lesson 2/Learning Event 3
This malfunction is most noticeable when you first apply the brakes.
As soon as the brakes are applied, the wheels tend to lock and the
tires slide on the road. Sometimes only one wheel will grab, while
at other times more than one will grab.
Grease, fluid, or grit on the brake lining is the primary cause of
this fault. With this condition the lining must be replaced.
If the brake shoes are binding on the anchors, they will snap out to
the drums when enough pressure is applied.
Loose spring Dbolts or improperly adjusted wheel bearings can cause
the position of the wheel to shift when the brakes are applied.
Loose lining on brake shoes and weak or broken brake shoe return
springs will allow the brakes to grab.
Brake drums that are out of round, scored, or cracked can also cause
brakes to lock up.
Squealing or grinding noises when the brakes are applied are not
Glazed lining that makes the brakes squeal should be replaced.
Scored brake drums and linings that are worn down to the rivets or
shoes will cause a grinding noise.
If the brake shoes, backing plates, or anchor pins are bent or
warped, the brakes will make an unusual sound when applied.