TM   9-2320-273-20 9-8.   BRAKE   SYSTEM   MAINTENANCE   TASK   SUMMARY. INITIAL SETUP APPLICABLE CONFIGURATIONS All. TEST EQUIPMENT EQUIPMENT CONDITION PARAGRAPH 9-13A. 5-37A. 9-27A  and  9-28A. 10-13A. None, 10-14A. SPECIAL TOOLS Snap Ring Pliers. Brake Spring Pliers. (See TM 9-2320-273-10). CONDITION DESCRIPTION Air Reservoirs Drained. Batteries Disconnected. Double Check Valve Removed. Hub and Drum Assembly Removed (M915). Hub and Drum Assembly Removed  (M916  Thru  M920). Wheel Raised OFF Ground; Park Brake Should Be Released  and  Wheels  Blocked. MATERIALS/PARTS (P/N) Liquid Teflon (Refer to Appendix C). Masking  Tape. Marking Pen. Soap and Water Solution. Seal,  1205-E-1409  (78500). GAA (Refer to Appendix C). Cotter Pin, K-227 (78500). Cotter Pin, 210490 (06853). Cotter Pin, 210492 (06853). PERSONNEL  REQUIRED SPECIAL  ENVIRONMENTAL  CONDITIONS TWO (MOS-63B20). Vehicle Parked on Level Ground. REFERENCES  (TM) GENERAL SAFETY INSTRUCTIONS TM  9-2320-273-10. Engine Off. LO  9-2320-273-12. Transmission  in  Neutral. TM  9-2320-273-20P. Park Brake Set. Wheels Blocked. REFERENCES    (TROUBLESHOOTING) Table 9-1. TASK NO. 1. 2. LIST  OF  TASKS TASK Trailer   Supply   Brake   Valve: a. Removal. b. Inspection  of  Lines  and  Fittings. c. Installation. d. Operational  Check. Trailer   Hand   Brake   Valve: a. Removal. TASK REF 9-17 9-17A 9-17B 9-17C 9-17D 9-18 9-18A TROUBLESHOOTING REF (TABLE) 9-1 9-1 3-20