TM-9-2320-273-10
TRUCK, TRACTOR, LINE HAUL; LIGHT EQUIPMENT TRANSPORTER; TRUCK CHASSIS; MEDIUM EQUIPMENT TRANSPORTER
TECHNICAL MANUAL; OPERATOR’S MANUAL
DECEMBER 2012
TM-9-2320-273-10 - Page 286 of 452
SLIDING FIFTH WHEEL AIR CONTROL SYSTEM (M915A1)
SYMPTOM
Fifth wheel cannot be locked in desired position when LOCK/UNLOCK control is
moved to LOCK position (tractor coupled to trailer).
MALFUNCTION
Obstructions between fifth wheel plate and slide track rack.
CORRECTIVE ACTION
Check for obstructions between fifth wheel plate and slide track rack. Clean
or remove objects from area as necessary and check again.
MALFUNCTION
Air cylinder has not had sufficient time to engage.
CORRECTIVE ACTION
Check air cylinder has sufficient time to engage. Leave LOCK/UNLOCK
control in LOCK position, wait for 10 seconds, and check again (WP 0005).
MALFUNCTION
Fifth wheel hung up between segments of slide track rack.
CORRECTIVE ACTION
Move LOCK/UNLOCK control to UNLOCK position, apply trailer brake
hand control, and place gear range selector in (1) or (R). Move tractor
slowly forward or backward an inch or two, stop and shift range selector to
NEUTRAL (N). Check fifth wheel is now locked. Release trailer brake hand
control.
MALFUNCTION
Air leak in fifth wheel air control system.
CORRECTIVE ACTION
If fifth wheel will not lock in position, check air line connections at cab
mounted control and at air cylinder under fifth wheel plate. Check for sound
of escaping air and loose fitting connections. If any leaks are found in air
system connections at control or air cylinder, notify supervisor.
TM 9-2320-273-10
0023
0023-12
Back to Top
