Recently some customer were confuse about 363-4454 and 363-4457 part and we found a definition of these two at follow, hope that could help.
1. 363-4457
This is a DO Type Seal which CAT has Replaced from Original Seal Group - HDDF 219-0615 i.e. seal with Rectangular Cross Section Rubber Ring from 30Apr2014, on account of heavy leakages reported.
To convert the Housing of HDDF 219-0615 suitable for DO type 363-4457 seal, it needs a separate Adaptor Ring ( 7 as shown in fig.)
This new design, accommodating DO type seal has following elements -.
1.#363-4454 : Duo-Cone Seal Group
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