CAT312 Excavator Carrier Roller | OEM Part # 4I7345, V990178V.

Genuine OEM carrier roller engineered specifically for CAT312 excavators. This critical undercarriage component is designed to support the upper track chain, maintain proper track tension, and distribute the machine's weight evenly during operation. Replace worn or damaged rollers with factory-spec parts to prevent costly track misalignment, reduce fuel consumption, and extend the lifespan of your excavator's undercarriage.

• OEM Precision: Manufactured to exact CAT specifications (Part # 4I7345, V990178V) for perfect fit and compatibility
• Heavy-Duty Construction: High-grade steel housing with heat-treated axle and sealed bearings for maximum resistance to impact, corrosion, and debris
• Advanced Sealing System: Double-labyrinth seals prevent water, dirt, and contaminants from entering the roller assembly, reducing maintenance needs and extending service life
• Optimized Load Distribution: Precision-engineered to support heavy loads while minimizing track wear and vibration
• Direct Replacement: No modifications required - bolt-on installation matches original equipment dimensions and mounting points

This carrier roller fits the following CAT excavator models:

• CAT312
• CAT312B
• CAT312BL
• CAT312C
• CAT312CL

Aftermarket carrier rollers may seem like a cost-effective alternative, but they often lack the quality control and engineering of genuine CAT components. Non-OEM parts can:

• Fail prematurely due to inferior materials and manufacturing processes
• Cause uneven track wear, leading to costly chain and sprocket replacements
• Create excessive vibration, increasing stress on the excavator's frame and hydraulic system
• Void your machine's warranty if installed
• Require frequent adjustments or replacements

Investing in genuine OEM carrier rollers ensures:

• Long-term reliability and consistent performance
• Protection of your CAT warranty
• Optimal undercarriage alignment and track tension
• Reduced overall maintenance costs over time
• Improved fuel efficiency by minimizing track drag

1. Safely lift the excavator using approved lifting points and support stands
2. Remove the track tension and loosen the track chain to access the carrier roller
3. Support the track chain with a jack or hoist to prevent it from falling during removal
4. Remove the mounting bolts and slide the worn roller out from under the track frame
5. Clean mounting surfaces and inspect for damage to the track frame or mounting brackets
6. Install new roller with OEM-grade hardware to specified torque values
7. Re-tension the track to CAT's recommended specifications and verify alignment

• Inspect carrier rollers daily for signs of wear, damage, or leaks
• Keep undercarriage clean to prevent debris buildup and premature wear
• Monitor track tension regularly to ensure proper roller engagement
• Replace rollers in pairs (left/right) to maintain balanced undercarriage performance
• Follow CAT's recommended maintenance schedule for undercarriage inspection and lubrication