JLG G12-55A Service Manual User Manual
Page 97

6-9
G10-55A, G12-55A
Transmission
5. Transmission overheating
(oil above 248° F (120° C)).
1. Low oil level.
1. Fill transmission to correct level
with hydraulic oil. Refer to
Section 2.4, “Fluid and
Lubricant Capacities.”
2. Clogged radiator.
2. Remove debris from the
radiator.
3. Transmission filled with incorrect
oil, or oil contaminated.
3. Drain transmission and fill to
correct level with hydraulic oil.
Refer to Section 2.4, “Fluid and
Lubricant Capacities.”
4. Excessive “roading.”
4. Stop and idle the engine.
5. Restriction in oil cooler hoses.
5. Replace cooler hoses.
6. Pump worn or damaged.
6. Repair or replace pump
assembly.
7. Engine thermostat stuck.
7. Replace engine thermostat.
Refer to Section 7.4.2,
“Thermostat Replacement.”
6. Grinding or “clunking” noise
from transmission.
1. Oil level too low.
1. Fill oil to correct level. Refer to
Section 2.4, “Fluid and
Lubricant Capacities.”
2. Repair or replace parts as
needed.
2. Transmission filled with incorrect
oil.
3. Drain transmission and fill to
correct level with hydraulic oil.
Refer to Section 2.4, “Fluid and
Lubricant Capacities.”
3. Incorrect clutch engagement.
4. Refer to Section 9.10.3,
“Transmission Solenoid Valves.”
4. Internal damage.
5. Repair or replace parts as
needed.
5. Broken diaphragm (torque
convertor).
6. Replace diaphragm (torque
convertor). Refer to Section
6.4.1, “Transmission Removal.”
6. Loose diaphragm (torque
convertor) mounting capscrews.
7. Tighten capscrews.
Problem
Cause
Remedy