CAT 108-4159 50mm Inner Diameter Bushing Bearing

CAT 108-4159 is a Caterpillar genuine single-row tapered roller bearing used in the differential drive pinion of loaders/excavators, gearbox second shaft, or transfer case output shaft. It bears radial and unidirectional axial loads, weighs approximately 0.85 kg, and is sold in single-shaft configurations. The following is professional structured information:

Core Technical Parameters (Professional Version)

Item Details
Basic Attributes: Model 108-4159, Single-row tapered roller bearing (imperial), Inner diameter φ40 mm (1.575 in), Outer diameter φ68 mm (2.677 in), Width 22.2 mm, Contact angle 12°, Radial clearance C2 (0.008-0.018 mm), Operating temperature -40℃ to +120℃

Key Dimensions: Inner ring large end diameter φ52 mm, Outer ring small end diameter φ58 mm, Taper angle α=12°, Number of rollers 12 Each (diameter φ8 mm, length 18 mm), cage material is stamped steel plate, center hole positioning tolerance +0.01/-0.005 mm, end face runout ≤0.02 mm

Material and Manufacturing Process: Rings/rollers are made of high carbon chromium bearing steel (SUJ2, HRC 60-62), surface carburized and quenched (hardened layer 0.8-1.2 mm), grease filling amount 5.2 g (Cat 106-3962 lithium-based grease), rotational accuracy P6 grade, limiting speed 4500 rpm

Compatible Models: Compatible with the front axle differential pinion of Cat 938K/950GC loaders, the slewing gearbox output shaft of 320GC/330GC excavators, or the accessory drive shaft support of C4.4/C7.1 engines

Assembly Fit: Shaft and inner ring interference fit (0.010-0.015 mm) The bearing housing and outer ring have a clearance fit (0.01-0.02 mm). A special press tool must be used for installation; striking the raceway surface is prohibited.

Installation and Maintenance Points: Before installation, clean the bearing and mounting holes, checking for rust, burrs, and dents. The inner ring must be positioned flush against the shaft shoulder, and the outer ring end face must be flush with the bearing housing stop (clearance ≤ 0.01 mm).

Adjust the preload torque according to the original manufacturer’s specifications: Recommended preload torque for pinion bearings is 15-20 N·m (with adjusting shims); preload torque for gearbox bearings is 8-12 N·m. Avoid overtightening, which can lead to excessive temperature rise, or undertightening, which can cause axial movement.

Maintenance Cycle: Check rotational flexibility, abnormal noise, and temperature rise every 1500 hours. Replace immediately if any abnormalities are found. It is recommended to replace the bearing during a differential/gearbox overhaul to prevent a decrease in gear meshing accuracy.