CAT 508-5838 RETAINER

CAT 508-5838 is a Caterpillar original equipment manufacturer (OEM) gearbox secondary shaft/differential retainer. It is a shaft retainer with a locking groove on the inner ring, compatible with the gearbox secondary shaft, differential input shaft, and hydraulic pump drive shaft of Cat 320D2/323D2 excavators and 966M loaders. Its core function is to axially position and fix 257-2177 cylindrical roller bearings, preventing axial movement of the bearings/gears. It is suitable for medium-high speed and medium-heavy load conditions. The following is professional structured information:

Core Technical Parameters (Professional Version)

Item Details
Basic Attributes
Model: 508-5838, Type: Shaft retainer (with locking groove/without ear), Compatible with Cat 320D2/323D2 excavator gearbox secondary shaft, 966M loader differential input shaft, 320D2 hydraulic pump drive shaft, Material: 65Mn Spring steel (blackened surface oxidation), free diameter φ80 mm, thickness 2.5 mm, width 6.0 mm, single weight approximately 0.15 kg, compatible shaft diameter φ80 mm, operating temperature -40℃ to +150℃, radial spring force ≥10 kN, ultimate shear strength ≥620 MPa, compatible groove diameter φ78.5 mm, groove width 6.2 mm

Key dimensions: Free diameter tolerance +0.10/-0.05 mm, thickness tolerance ±0.05 mm, width tolerance ±0.10 mm, opening clearance 3.5-4.0 mm, opening end chamfer 1.0×45°, locking groove depth 1.0 mm, locking groove width 2.0 mm, retaining ring edge roughness Ra≤0.8 μm, radial runout ≤0.05 mm, compatible shaft groove depth ≥2.7 mm, groove fillet radius ≤0.5 mm

Material and process: 65Mn Spring steel is quenched and tempered (hardness HRC 48-52), with a 5-8 μm thick black oxide layer for corrosion resistance. Elastic limit ≥1100 MPa, fatigue life ≥10^6 cycles. The locking groove edges are stress-relieved, with no burrs/cracks at the opening to prevent installation breakage. The locking groove is compatible with φ2 mm steel wire locking.

Compatible models: Cat 320D2/323D2/326D2 excavator gearbox secondary shaft, 966M/972M loader differential input shaft, D6K/D7E bulldozer hydraulic pump drive shaft. Used to fix 257-2177 cylindrical roller bearings, gears, or bushings. Compatible with φ80 mm shaft diameter, installed in the shaft end groove, mating with the bearing inner ring/shoulder.

Assembly fit: Interference fit with shaft groove (interference 0.10-0.15). (mm), after installation, the flatness of the retaining ring end face and the shaft end should be ≤0.1 mm, and the axial movement should be ≤0.05 mm. Use φ78 mm external snap ring pliers for installation. Do not strike. Use φ2 mm steel wire to secure the retaining ring through the locking groove to prevent it from falling off.

Installation and Maintenance Points:

Before installation, clean the shaft groove and check the retaining ring for deformation/cracks/elasticity failure. Use external snap ring pliers to pry open the retaining ring, align it with the groove, and slowly release it to ensure complete embedding. Insert the φ2 mm steel wire and secure it in the locking groove to prevent the retaining ring from loosening.

After installation, check that the retaining ring fits tightly in the groove without looseness. Check every 1000 hours. Replace the retaining ring immediately if it is deformed, loses elasticity, or is corroded.

Under heavy load/vibration conditions, check every 600 hours. When replacing, use the same model original part, verifying the dimensions/elasticity/locking groove specifications to avoid premature failure.