. MAINTENANCE MAINTENANCE PROCEDURE CHECK VIBRATION DAMPER 4 - 70 For the check and replacement damper, special tools a re required. Contact Komatsu Ltd. or its d istributo r in the territor y for th e replacement. It has to be replaced with a n ew one in the f ollowin g cases Mating mark ( 1) is hub inertia membe r of t he vibration dampe r to show an y misalignment betwee n the t wo. If this misalignmen dent fo und o n the damper metal sur face deepe (0.1in), then ( 2) the vibration damper must be replaced