Caterpillar 4J-4606 Wear Ring

The Caterpillar 4J-4606 wear ring is a plastic wear ring with a precise 139.70 mm outer diameter, designed to fit inside hydraulic cylinder bores on Cat equipment and to serve as a defined wear surface between the piston or rod and the cylinder wall. Its core function is to guide pistons or rods along the cylinder axis, maintain concentric alignment, and prevent metal-to-metal contact that would otherwise accelerate wear and disrupt the seal interface. Cat's official Parts Store identifies this item as an OEM wear-ring component and specifies that it is a plastic ring with a 139.70 mm outer diameter for hydraulic cylinder components. When installed in the appropriate cylinder configuration, the 4J-4606 provides necessary support around the piston to preserve clearance and cylinder performance. This part is cataloged as Cat 4J-4606 for hydraulic cylinder applications requiring a 139.70 mm outer-diameter wear ring.