CAT 2L-4444 Spherical Roller Bearing

CAT 2L-4444 is a Caterpillar single-row cylindrical roller bearing, primarily used in the front crankshaft/camshaft of Cat 3500 series diesel generator sets and C15/C18 engines. It is also used in the gearbox input shaft or transfer case output shaft of 988H loaders and D11 bulldozers. It mainly bears medium-to-high-speed, heavy-duty radial loads, limits radial runout, is suitable for oil lubrication, has a rated radial load of ≥120 kN, a limiting speed of 4800 rpm, and a fatigue life of ≥8500 hours, ensuring smooth operation of rotating parts and preventing increased clearance or seal failure in the transmission system. The following is structured technical and application information:

Core Technical Parameters
Item Details
Basic Attributes
Model 2L-4444, Single-row cylindrical roller bearing (including inner ring, outer ring, rollers, and stamped steel cage), suitable for Cat 3500 series generator crankshaft front end, C15/C18 engine camshaft, 988H loader gearbox input shaft, and D11 bulldozer transfer case output shaft. Material is GCr15 chromium bearing steel (integral quenching HRC 60-64). Cage is stamped steel plate. Operating temperature: -40℃ to +120℃. Single weight: approximately 1.25 kg. Suitable for SAE 15W-40 diesel engine oil lubrication. Rated radial load ≥120 kN, limiting speed 4800 rpm, fatigue life ≥8500 hours. Used to bear radial loads, limit radial runout, and ensure smooth operation of rotating parts.

Key Dimensions
Inner diameter 80.00 mm (3.150 mm) Dimensions: In diameter 125.00 mm (4.921 in, tolerance H7, +0.030/0 mm), outer diameter 125.00 mm (4.921 in, tolerance h6, 0/-0.022 mm), width 32.00 mm (1.260 in, tolerance ±0.12 mm), roller diameter 7.00 mm (28 rollers), roller length 28.00 mm, radial clearance C3 (0.030-0.050 mm), shaft fit tolerance k6 (+0.021/+0.002 mm), bearing housing fit tolerance H7 (+0.040/0 mm). Material and manufacturing process: GCr15 chromium bearing steel → forging → rough grinding → quenching (850℃ oil quenching) → low-temperature tempering (160℃) → fine grinding → assembly (rollers + stamped cage + inner and outer rings) → rust prevention treatment, hardened layer depth 2.2-2.8 mm. With a diameter of 80 mm, it possesses high hardness, high wear resistance, and fatigue resistance, suitable for medium- and high-speed, medium- and heavy-duty operating conditions, and can withstand pure radial loads.

Compatible models: Cat 3500 series diesel generator sets (G3512/G3516), C15/C18 engines, 988H/992K loaders, D11/D10 bulldozers, 793 mining trucks. Used in crankshaft front ends, camshafts, gearbox input shafts, transfer case output shafts, etc., to withstand radial loads, limit radial runout, and ensure smooth component operation.

Assembly fit: Compatible with 80 mm diameter shafts (tolerance k6, +0.021/+0.002 mm), bearing outer diameter and bearing housing fit tolerance H7 (+0.040/0 mm), bearing end face and mounting surface contact area ≥90%, radial clearance controlled within 0.030-0.050 mm after installation, compatible with M24×2 bolts (grade 10.9, preload torque…). (150-170 N・m)
Installation and Maintenance Points:
Before installation, clean the bearing, journal, and bearing housing. Check for scratches, rust, and cracks on the surfaces. Measure the bearing inner diameter and journal diameter, and the bearing outer diameter and bearing housing inner diameter to ensure the fit meets requirements. The bearing housing surface roughness Ra ≤ 1.6 μm, the end face should be flat and free of deformation, and the journal fillet radius ≤ 2.0 mm to avoid stress concentration at the roller ends.

Use the cold mounting method for installation, ensuring the bearing and journal are coaxial. Do not directly strike the bearing end face with a hammer to prevent damage to the rollers or cage. After installation, check the bearing’s rotational flexibility to ensure there is no jamming or abnormal noise, and the radial clearance meets C3 requirements.

Maintenance Recommendations: Check the bearing’s wear condition every 2000 hours. If the raceway wear is > 0.12 mm or if roller pitting or cage deformation occurs, replace the bearing immediately. Regularly change the machine oil to keep it clean and prevent oil contamination from accelerating bearing wear, affecting rotational accuracy and load-bearing capacity.