13. Good drum brake performances comes from improving a shoe's relationship with the drum. Shoes have to meet the drum so 100-percent of the friction material makes contact. If you have backing plate or shoe distortion, linings don't hit the drum 100-percent. Wheny ou remove worn shoes, examine wear patterns. When shoes contact drums at an angle, backing plate and axle flange run-out need a closer look. Brake shoes must sometimes be arced (machined) by a brake shop for uniform contact.