Auto Wheel & Tractor Bearing 256908 (38-1250) | Double Row Angular Contact Ball Bearing 37×72×37mm — Wheel Hub & Agricultural Tractor, OEM & Wholesale Supply

Understanding the 256908 Part Number

The 256908 follows the Chinese national standard (GB) double row angular contact ball bearing numbering convention. The 25 prefix identifies this as a 25° contact angle series double row angular contact ball bearing — providing a steeper contact angle than the 156704 (15° single row) also in the range, and therefore superior bidirectional axial load capacity. The double row construction allows a single bearing to handle the full combined load profile of a wheel hub assembly without requiring a paired bearing arrangement.

Why the Width Equals the Bore: 37mm × 37mm

A distinctive geometric feature of the 256908 is that its width (37mm) equals its inner diameter (37mm):

The 1:1 width-to-bore ratio is characteristic of double row angular contact ball bearings designed for wheel hub applications. The wide construction (37mm width for a 37mm bore) is necessary to accommodate two rows of balls at the 25° contact angle, providing the bearing with sufficient axial load capacity in both directions to handle the full range of wheel hub loads — radial from vehicle weight, and axial from cornering and braking forces.

Angular Contact Ball Bearings in the Range: 156704 vs 256908

Nexans Bearings supplies two angular contact ball bearings in the auto wheel and tractor bearing range:

The 256908 provides significantly higher combined load capacity than the 156704 due to its larger size, double row construction, and steeper 25° contact angle. For motorcycle and small equipment hubs (20mm bore), use the 156704. For automotive and tractor wheel hubs (37mm bore), use the 256908.

Why Double Row Angular Contact Ball Bearings for Wheel Hubs

Double row angular contact ball bearings like the 256908 are specified for automotive and tractor wheel hub applications because they uniquely combine:

Complete Auto Wheel & Tractor Bearing Range — Angular Contact Series

Complete Tractor & Auto Wheel Hub Bearing Range — All Types

Nexans Bearings supplies the full range of auto wheel and tractor hub bearings:

✅ Nexans Bearings supplies all nine sizes across three bearing types — source your complete auto wheel and tractor hub bearing range from a single supplier. Contact us for a combined quote across all part numbers.

Quick selection guide by bore size: 20mm bore → 156704 (single row angular contact, motorcycle/small equipment) 37mm bore → 256908 (double row angular contact, auto/tractor hub) 38mm bore → confirm OD: 72mm → 9036338006 / 73mm → 44300SAA003 / 74mm → 9036938003 40mm bore → 9036340066 43mm bore → confirm OD: 79mm → 44300S5A008 / 82mm → 9036343008 45mm bore → 44300S47008

Cross Reference Numbers

Contact our technical team with your application details for confirmed international cross-references.

Vehicle & Equipment Compatibility

The 256908 double row angular contact ball bearing is used in wheel hub applications requiring a 37mm bore and high combined radial and bidirectional axial load capability:

Please confirm exact fitment using part number 256908 or contact our technical team with your equipment make, model, and year.

Product Overview

The 256908 is a sealed double row angular contact ball bearing manufactured to OE-equivalent specifications for automotive wheel hub and agricultural tractor hub applications. With a 37mm bore, 72mm outer diameter, and 37mm width, it is the only double row angular contact ball bearing in the Nexans Bearings auto wheel and tractor hub range — providing the highest combined load capacity of any angular contact bearing in the series through its double row construction and 25° contact angle.

The 37mm width equal to the 37mm bore reflects the wide construction required to accommodate two rows of balls at the 25° contact angle — a design that delivers bidirectional axial load capacity in a single sealed unit, eliminating the need for paired bearings or separate thrust bearing arrangements in the hub assembly.

At 550g, the 256908 offers robust construction for demanding automotive and tractor wheel hub environments, with the full angular contact performance needed for combined radial, axial, and moment loads.

This bearing delivers:

• Bidirectional axial load capacity — double row 25° angular contact handles thrust in both directions simultaneously

• High radial load capacity — two rows of balls share the full radial load from vehicle weight

• Moment load resistance — double row arrangement resists hub tilting from cornering and uneven terrain

• Single-unit hub solution — no paired bearings required; one bearing handles all load directions

• Superior contamination resistance — sealed construction blocks road grit, water, and mud

• Excellent grease retention — factory pre-lubricated, sealed for life under normal operating conditions

• OE-equivalent fit — manufactured to GB specification for direct replacement of 256908

• Chrome steel durability — GCr15 / 52100 material provides high hardness and fatigue strength

Sourced from Nexans Bearings' trusted manufacturing network — including leading Chinese bearing brands QC, C&U, ZWZ, TWB, and ZWA — every unit undergoes strict dimensional and quality inspection before dispatch.

Why Source from Nexans Bearings

OEM & Private Label Service

Nexans Bearings provides a complete OEM and private-label program for automotive and agricultural machinery parts distributors:

• Custom Packaging Design — your brand, your box, your label

• Laser Marking — part numbers (256908) and logos etched directly on the bearing

• GB Spec Matching — dimensional validation against OEM specification

• Clearance & Grade Selection — specify C0/C2/C3 clearance and P0–P5 precision grade per your application

• Flexible MOQ — suitable for startups and established importers alike

• Full Documentation — inspection reports, material certificates, and packing specifications per order

• Dedicated Account Management — assigned support for OEM and high-volume clients

Frequently Asked Questions

Q: What are all the part numbers for this bearing?

This bearing is referenced as 256908 (GB standard part number) and 38-1250 (NKS reference).

Q: What are the exact dimensions of the 256908?

The dimensions are: Inner Diameter 37mm × Outer Diameter 72mm × Width 37mm. Note that the width equals the bore diameter — both are 37mm.

Q: What type of bearing is the 256908?

The 256908 is a double row angular contact ball bearing with a 25° contact angle. It is not a deep groove ball bearing. The double row angular contact design provides bidirectional axial load capacity and high moment load resistance in a single sealed unit.

Q: What is the difference between the 256908 and the 156704?

Both are angular contact ball bearings, but: 156704 = single row, 15° contact angle, 20mm bore (for motorcycle/small equipment hubs) / 256908 = double row, 25° contact angle, 37mm bore (for automotive/tractor wheel hubs). The 256908 is larger, heavier-duty, and handles loads in both axial directions simultaneously.

Q: Why does the 256908 have a width equal to its bore (both 37mm)?

The 1:1 width-to-bore ratio is characteristic of double row angular contact ball bearings for wheel hub applications. The wide 37mm construction accommodates two rows of balls at the 25° contact angle, providing the bearing with sufficient bidirectional axial load capacity for wheel hub service.

Q: Can the 256908 replace two single row angular contact bearings?

Yes — the double row construction of the 256908 is designed to handle axial loads in both directions within a single unit, effectively replacing a back-to-back or face-to-face pair of single row angular contact bearings in many hub applications. Confirm with our technical team for your specific application.

Q: What equipment uses the 256908 bearing?

The 256908 is used in automotive wheel hubs and agricultural tractor wheel hubs with a 37mm bore. Contact us with your equipment make and model to confirm exact fitment.

Q: Is the 256908 pre-lubricated?

Yes. The bearing is factory pre-lubricated with grease and sealed on both sides. Under normal operating conditions, no relubrication is required during the bearing's service life.

Q: Do you supply the complete range of auto wheel and tractor hub bearings?

Yes. Nexans Bearings supplies all nine variants across three bearing types. Contact us for a combined quote across the full range.

Q: Do you offer OEM or private label for this bearing?

Yes. We provide full OEM and private-label services including custom packaging, laser-etched branding, and GB-compliant documentation. Contact our sales team to discuss your requirements and MOQ.

Q: What is the minimum order quantity (MOQ)?

MOQ is flexible and negotiable. We welcome both trial orders and large-volume contracts. Contact us for a tailored quote.

Q: How quickly can you ship?

We maintain ready stock of auto wheel and tractor hub bearings including the 256908. Orders are typically dispatched within 3–7 business days. Expedited shipping is available upon request.

Q: Do you provide quality certifications?

Yes — dimensional inspection reports, material certificates, and packing specifications are available upon request for every order.

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