Auto Wheel & Tractor Bearing 256905 (38-1247) | Double Row Angular Contact Ball Bearing 25×55×30mm — Wheel Hub & Agricultural Tractor, OEM & Wholesale Supply

Product Specifications

Understanding the 256905 Part Number

The 256905 carries size code 05 — the entry point of the GB 25-69xx series as supplied by Nexans Bearings. The size code increments from 05 (25mm bore) → 06 (28mm bore) → 07 (34mm bore) → 08 (37mm bore), with all four sharing the same 25° contact angle and double row construction.

GB 25-69xx Series: All Four Bore Sizes — Complete Series Comparison

⚠️ Critical series note: The four bearings in the GB 25-69xx series do not share a common width. The 256905 (25mm bore) has a 30mm width, the 256906 (28mm bore) has a 42mm width, and the 256907 and 256908 both have a 37mm width. Never assume width is constant across the series — always verify the full dimensions when ordering.

Width-to-Bore Ratio Across the Full 25-69xx Series

The width-to-bore ratio across the 25-69xx series follows a non-monotonic pattern: it rises from 1.2:1 (256905) to a peak of 1.5:1 at 256906, then decreases to 1.09:1 (256907) and 1.0:1 (256908). The 256906 (28mm bore, 42mm width) holds the highest width-to-bore ratio in the series — not the smallest-bore 256905. This reflects individual engineering design decisions for each bore size rather than a simple linear progression. When sourcing any bearing in this series, always confirm the full three-dimensional specification (bore × OD × width) rather than inferring width from bore size alone.

Angular Contact Ball Bearings in the Range: Full Series

Complete Auto Wheel & Tractor Hub Bearing Range — All Types

Nexans Bearings supplies the full range of auto wheel and tractor hub bearings across three bearing types:

✅ Nexans Bearings supplies all twelve 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.

Quick selection guide by bore size: 20mm bore → 156704 (single row angular contact, motorcycle/small equipment) 25mm bore → 256905 (double row angular contact, auto/tractor hub) 28mm bore → 256906 (double row angular contact, auto/tractor hub) 34mm bore → 256907 (double row angular contact, auto/tractor hub) 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 256905 double row angular contact ball bearing is used in wheel hub applications requiring a 25mm bore and high combined radial and bidirectional axial load capability:

Please confirm exact fitment using part number 256905 or contact our technical team with your equipment make, model, and year.

Product Overview

The 256905 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 25mm bore, 55mm outer diameter, and 30mm width, it is the entry-point member of the GB 25-69xx series — carrying size code 05 and serving the smallest hub shaft size in the series.

The 30mm width exceeding the 25mm bore (width-to-bore ratio 1.2:1) reflects the double row angular contact construction required for bidirectional axial load capacity at the 25mm shaft size. Notably, the 256905's 1.2:1 ratio is lower than the 256906's peak ratio of 1.5:1 — demonstrating that the width-to-bore relationship across the 25-69xx series is non-monotonic, with the 256906 (28mm bore, 42mm width) representing the widest-relative-to-bore design in the series.

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 256905

• 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 (256905) 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 256905 (GB standard part number) and 38-1247 (NKS reference).

Q: What are the exact dimensions of the 256905?

The dimensions are: Inner Diameter 25mm × Outer Diameter 55mm × Width 30mm.

Q: How does the 256905 fit within the GB 25-69xx series?

The 256905 (size code 05) is the entry-point member of the series as supplied by Nexans Bearings. The full series: 256905 (25mm bore) → 256906 (28mm bore) → 256907 (34mm bore) → 256908 (37mm bore). All four share a 25° contact angle and double row construction, but have different outer diameters and widths.

Q: Why does the 256905 have a 30mm width while the 256906 has a 42mm width, even though 256905 has a smaller bore?

The width-to-bore ratio across the 25-69xx series is non-monotonic — the 256906 (28mm bore, 42mm width, ratio 1.5:1) has the highest ratio in the series, not the smallest-bore 256905 (25mm bore, 30mm width, ratio 1.2:1). This reflects individual engineering design decisions for each bore size. Always verify the full dimensions when ordering any bearing in this series.

Q: What equipment uses the 256905 bearing?

The 256905 is used in automotive wheel hubs and small agricultural tractor wheel hubs with a 25mm bore. Contact us with your equipment make and model to confirm exact fitment.

Q: Is the 256905 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 all four sizes in the 25-69xx series?

Yes — Nexans Bearings supplies all four bore sizes: 256905 (25mm), 256906 (28mm), 256907 (34mm), and 256908 (37mm). Contact us for a combined quote.

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 256905. 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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