Doosan DX60R Shop Manual page 102

Replace bearing.
Galling
Metal smears on roller ends because of overheating, lubricant
failure or overload.
Replace bearing - check seals and check for proper
lubrication.
Abrasive Step Wear
Pattern on roller ends caused by fine abrasives.
Clean all parts and housings, check all parts and housings,
check seals and bearings and replace if leaking, rough or
noisy.
General Maintenance Procedures
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Figure 4
Figure 5
Figure 6
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