The NTN 6311C3 Deep Groove Ball Bearing is a high-quality precision single-row bearing engineered for reliable rotation and combined radial and axial load support. Designed for versatility, durability, and high-speed operation, it is widely used in automotive components, industrial machinery, and mechanical systems requiring smooth motion and long service life.

Technical Specifications

Notes:
✔ C3 internal clearance means slightly more space between the inner ring and outer ring, which helps accommodate thermal expansion and lighter preload in high-speed or high-temperature applications.
✔ This bearing is open (no seals/shields) — appropriate for applications where the assembly provides lubrication and protection.

Product Overview

Deep groove ball bearings are one of the most versatile bearing types due to their simple design and ability to support:

✔ Radial loads in both directions
✔ Moderate axial loads in both directions
✔ High-speed rotation with low friction and low vibration
✔ Easy mounting and low maintenance

The NTN 6311C3 combines robust load capacity with a larger internal clearance (C3), making it suitable for systems where thermal effects, expansion, or heavier running loads are present.

Features & Benefits

• Versatile Load Handling: Handles radial and axial loads simultaneously.

• High-Speed Capability: Good operational speeds with appropriate lubrication.

• C3 Internal Clearance: Extra clearance for expanded operating conditions (e.g., heat/expansion).

• Robust Construction: Hardened steel balls and rings with pressed-steel cage for durability and long life.

• Open Design: Suitable for applications where grease and sealing are handled externally.

Typical Uses & Applications

This bearing’s 55×120×29 mm size and design make it suitable for a wide range of dimension-matched applications:

⚙️ Industrial & Mechanical

• Electric motors and generators

• Gearboxes and gear reducers

• Conveyor rollers

• Pumps and compressors

• Machine tools and power transmissions

Automotive & Vehicle Systems (Dimension-Based)

Deep groove bearings like the 6311C3 are selected by bearing size and load requirement, not by vehicle model/year directly. Because OEM catalogs use bearing codes/dimensions rather than a generic “6311C3” for vehicles, you match it by:

📌 Confirm the bearing’s dimensions and C3 clearance in the vehicle’s parts manual or by checking the original bearing code on the part. If the specified size is 55 mm bore × 120 mm outer × 29 mm width with additional clearance requirements, then the 6311C3 is a correct replacement.

Applications in vehicles commonly include:

• Alternator shafts

• Water pump pulleys

• Tensioner/idler pulleys

• HVAC blower motor shafts

• Transmission accessory shafts

Always verify with your VIN and parts catalog for exact bearing codes used in your vehicle’s assemblies.

Related Brand/Equivalent Part Numbers

When searching for compatible bearings with the same dimensions (55×120×29 mm and C3 clearance), you may also see:

• SKF: 6311/C3 deep groove ball bearing

• FAG 6311 C3 (similar open design)

• KOYO 6311C3 deep groove ball bearing

• NSK 6311C3 deep groove ball bearing

⚠ Always confirm dimensions and specific C3 clearance before substituting brands.

Fitment & Selection Tips

✔ Dimension Match: Confirm bore (55 mm), outer diameter (120 mm), and width (29 mm).
✔ Internal Clearance: Use C3 variants when thermal expansion or higher operating speeds are anticipated.
✔ Seal/Lubrication Needs: If environmental exposure is present, consider sealed/shielded variants (e.g., 6311-2RS or 6311ZZ) instead of open type.
✔ Check OEM Codes: For automotive queries, always verify the exact bearing code recommended by the manufacturer or OEM parts catalog.