Caterpillar (Cat) TRS8, S45/S45, 7-10 Ton Mini Excavators

The TRS4 is designed for Cat mini excavators with an operating weight of 3 to 4 tonnes and is fitted to the excavator arm via a Pin-On or Pin-Grabber mount, that is, a mechanical pin connection rather than a hydraulic locking system. Above the quick coupler itself sits the rotation unit, which turns the attached tool around its own axis, and a tilt mechanism that angles the tool sideways.

A tiltrotator such as the TRS4 allows the bucket or attachment to be turned and tilted to any angle without repositioning the excavator itself, which saves time especially when profiling slopes, grading and laying pipe to a set fall. With quick couplers and tiltrotators, it is the standard and mount type that determine the fit to the carrier machine, not any output rating of the unit itself.

When buying a used tiltrotator such as the TRS4, the condition of the Pin-On pins and their bushings matters, since considerable forces pass through this mechanical mount. The rotation drive should be checked for smooth, even running through the full turn, the tilt cylinders for tightness, and the hydraulic rotary union, which keeps oil flowing to the attachment during rotation, for leaks.