CAT 319-3477 TRUNNION-GD

CAT 319-3477 YM is a Caterpillar General Duty (GD) trunnion assembly, suitable for articulated, swaying, or support parts of loaders, excavators, and other equipment. It is designed for reliable transmission and positioning under light to medium load conditions. The following are the original manufacturer’s core specifications and application information, excluding replacement parts (Cat®…).

Core Technical Parameters

Item Details
Part Model: CAT 319-3477 YM (GD Universal Trunnion)

Product Type: Integral solid trunnion with spherical/cylindrical mating surfaces + positioning structure

Material: Low-alloy high-strength steel, integral forging + quenching and tempering treatment

Surface Treatment: Precision grinding + surface strengthening treatment, suitable for medium to light load wear resistance requirements

Hardness: Surface HRC 50–55, Core HB 260–300

Weight: Approx. 3.3 kg (7.28 lbs)

Operating Temperature: -40℃ ~ +100℃

Key Dimensions (Metric/Imperial): Body diameter common specifications 50–60 mm, spherical diameter suitable for corresponding bearings/bushings, effective length matched according to model, with positioning grooves/threaded holes at both ends

Matching Requirements: Suitable for corresponding inner diameter bushings/bearings, recommended clearance 0.04–0.08 mm

Load Capacity: Rated radial load ≥ 80 kN, suitable for medium impact and low-frequency oscillation conditions.

Lubrication Design: Equipped with axial lubrication holes + radial oil outlet holes, supporting centralized lubrication and reducing friction and wear.

Structure and Core Characteristics: Universal high-strength structure; low-alloy forging process, seamless, tensile and shear strength meets the requirements of medium and light load equipment, suitable for non-extreme impact operation scenarios, not easily deformed or broken.

High Adaptability: As a GD universal trunnion, it can be adapted to the boom, connecting rod, bucket, and other hinge points of various Caterpillar small and medium-sized loaders and excavators, offering high versatility and convenient replacement of stock.

Reliable Lubrication and Positioning: The central lubrication channel ensures sufficient oil supply to the friction surface, and the positioning structure at both ends can be equipped with snap rings and baffles to prevent the trunnion from shifting during operation, ensuring connection stability.

Compatible Models and Application Scenarios: Loaders: 906H, 907H, 908H, and other small and medium-sized models, used for boom, rocker arm, and connecting rod hinge parts.

Excavators: Small tonnage models such as 305.5E2, 306E2, and 307E2, compatible with hinge points on the boom, bucket, and connecting rod.

Core Applications: Replaces worn trunnions, restores hinge clearance, and resolves issues such as equipment jamming and abnormal noise. Suitable for medium to light loads and moderate workloads.