COUPLER SYSTEMS
COUPLER EAR-TO-LUGGING INTERFERENCE
Identification, Correction & Acceptance Criteria
Summary: When mounting a TRK coupler onto an attachment, the coupler ears may experience interference with the attachment lugging due to varying dimensions. This article explains how to identify that interference and then correct and modify it for proper seating.
Applies to: If you are connecting a bucket or attachment to a coupler and the attachment does not seat as expected—such as the coupler ear contacting the attachment lugging prematurely, producing a noticeable sound and leaving a gap when the hook is not fully seated over the pin—this article addresses that condition.
Final Acceptance Criteria
- Specified clearance on both sides of ear/lugging
- Confirmed full seating
- Free pin engagement without using the pin to force alignment
- No remaining contact/interference
Technical bulletin
The procedure establishes the required clearance, acceptable material removal limits, inspection requirements, and final acceptance criteria.
Related documents
Download the TRK Attachments 2026 Catalogue (PDF)