TM   10-3930-638-24&P 2-43. SERVICE BRAKE MAINTENANCE (cont) a. Service Brake Assembly (cont). STEP LOCATION ITEM ACTION REMARKS ADJUSTMENT (cont) 15 a. (cont) b. c. Brake  pedal Actuate To center brake shoe and lining assemblies in drum Two  cam  adjusting Turn as shown To expand brake shoes until slight drag can bolts be felt while drum is rotating Two  cam  adjusting Turn as shown To contract brake shoes until drum rotates bolts freely  (no  drag) NOTE After  adjustment,  repeat  steps  1  through  15  above  for  remaining brake  assemblies. 2-287