CAT 396-3975 416 mm Outer Diameter Seal Retainer

CAT 396-3975 are Caterpillar front wheel and brake system sealing retainers (seal cages), compatible with the front wheels and brake assemblies of Cat 783B/784B/785 series mining trucks. With an outer diameter of 416 mm, their core function is to secure the wheel end seals, prevent grease leakage and dust/moisture intrusion, and provide stable sealing and positioning for the wheel end bearings. The following is precise technical and application information from parts.cat.com.

Core Parameters (Precise Version)

Item Details
Basic Attributes Model 396-3975, Seal Retainer, used for front wheels and brake assemblies, to fix wheel end seals and prevent seal displacement, single unit usage 1 piece/wheel end
Compatible Models Cat 783B, 784B, 784C, 785, 785B, 785C, 785D, 785G Mining trucks (including tractors), compatible with front wheel hubs and brake disc assemblies

Material and Process Gray cast iron (HT250), hardness HB 180-220, surface rust prevention treatment, bolt hole tolerance H8, positioning stop tolerance H7, sealing groove precision IT12

Key Dimensions Outer diameter 416 mm (16.38 in), inner diameter 270.26 mm (10.64 in), width 43.94 mm (1.73 in), bolt hole distribution circle diameter 380 mm, 10 bolt holes, 18 mm diameter, weight approximately 12.5 kg. Core Functions and Applications:

Sealing and Fixing: Securely clamps the main wheel end seal, preventing circumferential rotation and axial movement of the seal during vehicle movement or braking. Suitable for heavy-duty, high-frequency braking conditions in mining trucks, withstanding axial positioning force ≤30kN.

Protective Isolation: Forms a sealed cavity with the wheel hub and brake disc, preventing mine dust, sand, and rainwater from entering the wheel end bearing and preventing grease leakage. Suitable for operating temperatures from -30℃ to +120℃.

Typical Location: Inside the front wheel hub of a mining truck, between the brake disc and the bearing housing, providing axial positioning for the double-row tapered roller bearing at the wheel end (e.g., 293-1986), ensuring coaxiality between the bearing and the wheel hub, and reducing wheel end vibration and wear.

Installation and Maintenance Points

Before Installation: Clean the retaining ring, wheel hub, and brake disc sealing surfaces, checking for cracks, deformation, or rust; install the seals (NBR material, hardness 70 Shore A), and apply NLGI 2 lithium-based grease.

During Installation: Align the positioning stop, tighten the bolts evenly (torque 80-100 N·m), check the runout of the retaining ring end face ≤0.2 mm, and ensure the sealing surfaces are in perfect contact without gaps.

Maintenance and Replacement: Check the seal wear and bolt tightness every 500 hours. Replace immediately if oil leakage, seal aging, or retaining ring deformation occurs. Do not use sealant to replace seals, as this will affect the sealing effect.