According to the bearing experts at Timken, differential and transmission repairs on a heavy-duty vehicle can be expensive and may result in significant downtime. However, problems with these driveline gearboxes can be detected at an early stage. The following conditions during normal operation of the vehicle may be early signs of a driveline problem:
Operating conditions:
Noise—may indicate damage to a driveline component
Vibration—may indicate surface wear/roughness of a driveline component; may be felt on the gearshift lever)
Shaking—may indicate a loosened component; may also be felt on the gearshift lever
Difficulty shifting gears—may indicate a transmission component problem
Higher-than-normal operating temperature—high temperatures during other than heavy-pulling conditions may indicate low lubricant level or worn-out lubricant
Low lubricant level—may indicate lubricant leak, underfill or overuse
Lubricant leak on outside of gearbox—may indicate a seal problem
Lubricant conditions:
Color—gray or “milky” appearance could indicate presence of water
Consistency—thick oil may indicate lubricant breakdown
Presence of metallic debris/contaminants—may indicate excessive wear or spalling of gear teeth or bearing surfaces
Burnt/discolored area on outside of differential or transmission housing—indicates extremely high temperature or low lubricant level
Risks of higher maintenance and repair costs increase if these warning signs are ignored and if further inspection and/or maintenance is not performed, Timken warns. Technicians need to develop a keen eye for detecting these signs and symptoms.
