Auto Wheel & Tractor Bearing 256708 (38-1243) | Double Row Angular Contact Ball Bearing 42×75×37mm — Wheel Hub & Agricultural Tractor, OEM & Wholesale Supply

Product Specifications

Understanding the 256708 Part Number

The 256708 is the sole representative of the GB 25-67xx series in the Nexans Bearings range — a third distinct GB double row angular contact series alongside the 25-68xx series (256805/256807/256808) and the 25-69xx series (256905–256908). All three series share the same 25° contact angle and double row construction but follow different GB dimensional standards.

⚠️ The Lowest Width-to-Bore Ratio in the Entire Range: 256708's Narrow Profile

The 256708 holds the lowest width-to-bore ratio of any bearing in the Nexans Bearings auto wheel and tractor hub range:

At 0.88:1, the 256708 has the most compact axial profile relative to its bore size of any bearing in the range — even more compact than the 256805 (0.92:1). Despite carrying the largest bore (42mm) in the angular contact range, its 37mm width is narrower than that bore, reflecting a design optimised for hub assemblies where axial space is limited at this shaft size.

Three GB Series of Double Row Angular Contact Ball Bearings

The Nexans Bearings range includes double row angular contact ball bearings from three distinct GB series — all sharing 25° contact angle and double row construction:

The three series are not interchangeable even where bore sizes overlap. Always identify the correct series by confirming the full three-dimensional specification (bore × OD × width) and the GB series designation.

Width-to-Bore Ratio Across All Double Row Angular Contact Bearings — Complete Ranking

Across all eight double row angular contact ball bearings in the range, width-to-bore ratios span from 0.88:1 (256708) to 1.50:1 (256906). Only two bearings have sub-1:1 ratios — 256708 (0.88:1) and 256805 (0.92:1) — both from the 25-67xx and 25-68xx series respectively. The 25-69xx series (256905–256908) spans the widest ratio range (0.92–1.50:1) and includes the highest ratio bearing (256906).

256708 vs 256808: Adjacent Bore Sizes, Different Series

The 256708 (42mm bore, 25-67xx) and 256808 (40mm bore, 25-68xx) are the two largest-bore double row angular contact ball bearings in the range:

The 256708 and 256808 differ in bore (42mm vs 40mm), OD (75mm vs 74mm), width (37mm vs 40mm), and GB series. Despite their close dimensions, they are not interchangeable. Confirm hub shaft bore precisely — 40mm shaft → 256808 / 42mm shaft → 256708.

Angular Contact Ball Bearings in the Range: Full Series (All Eight)

Complete Auto Wheel & Tractor Hub Bearing Range — All Types

✅ Nexans Bearings supplies all sixteen 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) 25mm bore → confirm OD: 52mm housing → 256805 / 55mm housing → 256905 28mm bore → 256906 (double row angular contact) 34mm bore → 256907⚠️ confirm shaft is exactly 34mm 35mm bore → 256807⚠️ confirm shaft is exactly 35mm 37mm bore → 256908 (double row angular contact) 38mm bore → confirm OD: 72mm → 9036338006 / 73mm → 44300SAA003 / 74mm → 9036938003 40mm bore → confirm type: angular contact → 256808 / deep groove ball → 9036340066 42mm bore → 256708 (double row angular contact, 25-67xx series) 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

Please confirm exact fitment using part number 256708 and verify hub shaft diameter is exactly 42mm and housing bore is 75mm. Contact our technical team with your equipment make, model, and year.

Product Overview

The 256708 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 42mm bore, 75mm outer diameter, and 37mm width, it is the largest-bore double row angular contact ball bearing in the Nexans Bearings range — and the sole representative of the GB 25-67xx series, the third distinct GB double row angular contact series in the range alongside the 25-68xx and 25-69xx series.

Its defining characteristic: at 0.88:1, the 256708 holds the lowest width-to-bore ratio of any bearing in the entire range — its 37mm width is narrower than its 42mm bore, making it the most axially compact bearing relative to shaft size across all sixteen products. Together with the 256805 (0.92:1), it is one of only two bearings in the range with a sub-1:1 width-to-bore ratio, reflecting a design optimised for hub assemblies where axial space is constrained at larger shaft diameters.

This bearing delivers:

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

• Compact narrow profile — 37mm width (sub-bore at 42mm) suits axially constrained hub assemblies

• 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 256708

• 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

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

• Laser Marking — part numbers (256708) 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 256708 (GB standard part number) and 38-1243 (NKS reference).

Q: What are the exact dimensions of the 256708?

Inner Diameter 42mm × Outer Diameter 75mm × Width 37mm.

Q: Why is the width (37mm) narrower than the bore (42mm)?

The 0.88:1 width-to-bore ratio is the design characteristic of the GB 25-67xx series at the 42mm bore size. The narrow 37mm profile is engineered for hub assemblies with limited axial space at this shaft diameter, while the 25° double row angular contact geometry still provides full bidirectional axial load capacity. The 256708 holds the lowest width-to-bore ratio of any bearing in the Nexans Bearings range.

Q: What is the GB 25-67xx series and how does it differ from 25-68xx and 25-69xx?

All three are GB double row angular contact ball bearing series with a 25° contact angle, but follow different dimensional standards. In the Nexans Bearings range: 25-67xx (256708) = 42mm bore / 25-68xx (256805/256807/256808) = 25/35/40mm bores / 25-69xx (256905–256908) = 25/28/34/37mm bores. The series designations (67/68/69) indicate different GB dimensional families.

Q: What is the difference between the 256708 and 256808?

256708: 42mm bore, 75mm OD, 37mm width, GB 25-67xx, width:bore 0.88:1. 256808: 40mm bore, 74mm OD, 40mm width, GB 25-68xx, width:bore 1.00:1. Different bore, OD, width, and series — not interchangeable. Select by hub shaft bore: 40mm → 256808 / 42mm → 256708.

Q: Is the 256708 the largest angular contact bearing in the range?

Yes — the 256708 (42mm bore) is the largest-bore double row angular contact ball bearing in the Nexans Bearings auto wheel and tractor hub range.

Q: What equipment uses the 256708 bearing?

The 256708 is used in automotive wheel hubs and medium-to-large agricultural tractor wheel hubs with a 42mm bore and 75mm housing bore. Contact us with your equipment make and model to confirm exact fitment.

Q: Is the 256708 pre-lubricated?

Yes — factory pre-lubricated with grease, sealed on both sides. No relubrication required under normal operating conditions.

Q: Do you offer OEM or private label?

Yes — full OEM and private-label services. Contact our sales team.

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

Flexible and negotiable. Contact us for a tailored quote.

Q: How quickly can you ship?

Ready stock maintained. Orders typically dispatched within 3–7 business days.

Q: Do you provide quality certifications?

Yes — dimensional inspection reports, material certificates, and packing specifications available on request.

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