TM 9-2320-302-20
0012 00-1
BRAKE SYSTEM TROUBLESHOOTING
0012 00
Table 1. Brake System Troubleshooting Procedures.
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
1. Vehicle Does Not Slow Down Quickly Enough
When Brakes Are Applied.
1. Check for proper lubrication
and adjustment of brakes.
Lubricate brake system (TM 9-
2320-302-10) or adjust brakes
(WP 0139 00) as necessary.
2. Check for heat-damaged and
glazed brakeshoe linings.
Replace any damaged or glazed
brakeshoes (all brakeshoes must
be replaced on an axle) (WP
0135 00 or WP 0137 00).
3. Check
brake
drums
for
excessive heat damage, cracks,
scoring, and out-of-roundness.
Replace damaged brake drums
(WP 0165 00 or WP 0166 00).
4. Check for faulty air chambers.
Replace faulty air chamber(s)
(WP 0141 00 or WP 0142 00).
5. Check for air pressure leakage
to air chambers.
Replace air compressor (Notify
Direct Support Maintenance).
2. Brakes Do Not Release or Release Too Slowly.
1. Check for proper lubrication of
brake system.
Lubricate brake system (TM 9-
2320-302-10).
2. Check that foot valve returns to
fully released position.
Remove any debris interfering
with pedal travel.
3. Check exhaust ports on brake
foot valve, quick release valve,
and gladhand vent holes for
blockage.
Clear obstructions from exhaust
port(s) and vents (WP 0161 00).
4. Check for weak and broken
brakeshoe return springs.
Replace weak or broken springs
(WP 0135 00 or WP 0137 00).
5. Check for frozen brakeshoe
anchor pins.
Clean and lubricate sticking pins
or replace pins if damaged (WP
0135 00 or WP 0137 00).
6. Check for broken spring in air
chamber.
Replace air chamber (WP 0141 00
or WP 0142 00).
3. Brakes Are Uneven, Drag or Pull When
Applied.
1. Check for uneven adjustment
between axles.
Adjust brakes (WP 0139 00).
2. Check for proper wheel bearing
adjustment.
Adjust wheel bearings (WP
0165 00 or WP 0166 00).
3. Check for grease-saturated or
worn brake linings.
Replace brake linings (WP
0135 00 or WP 0137 00).
4. Check
for
out-of-round
brakedrum(s).
Replace brakedrum(s) (WP
0165 00 or WP 0166 00).
5. Check for worn s-cam or roller. Replace s-cam or roller (WP
0140 00).
