Views: 286 Author: Site Editor Publish Time: 2026-09-28 Origin: Site
Wheel bearing part numbers and size specifications help identify the correct bearing for a particular vehicle or mechanical application. Most wheel bearing specifications include three essential dimensions: inner diameter, outer diameter, and width. Certain bearing series also use identification codes that indicate their construction and dimensional characteristics.
For automotive parts distributors, repair technicians, and wholesale buyers, understanding these numbers is essential for selecting compatible replacement bearings. However, dimensional information alone is not always enough to guarantee interchangeability.
This guide explains how to read wheel bearing numbers, understand common size codes, identify bearing specifications, and avoid mistakes when sourcing automotive wheel bearings.
Wheel bearing part numbers are identification codes used to distinguish bearing types, dimensions, and specific product configurations. Some numbering systems contain recognizable dimensional information, while others require a manufacturer's technical catalog for accurate identification.
A bearing number typically consists of letters, numbers, or a combination of both. The structure depends on the bearing series and the numbering system used.
For example, DAC series bearings are commonly used in automotive wheel applications. Many DAC designations include numerical groups corresponding to the bearing's inner diameter, outer diameter, and width.
However, not all bearing numbers follow the same format. Some use standardized bearing designations, while others follow application-specific or manufacturer-specific numbering conventions.
A wheel bearing designation may provide information about:
1.Bearing type and internal construction.
2.Inner diameter or bore size.
3.Outer diameter and overall width.
4.Sealing or shielding configuration.
5.Internal clearance or other design variations.
These characteristics help distinguish bearings intended for different applications.
Suffixes may provide additional technical information, but their meanings are not universal. Buyers should always refer to the relevant product specifications before interpreting unfamiliar codes.
Many DAC wheel bearing part numbers follow a recognizable dimensional format. For example, DAC30600037 commonly identifies a double row angular contact wheel bearing with a 30 mm inner diameter, 60 mm outer diameter, and 37 mm width.
DAC series bearings are widely associated with automotive wheel applications where the bearing must support radial and axial loads.
The letters DAC identify the bearing series, while the numerical portion often represents its principal dimensions in millimeters.
Consider the designation DAC30600037.
The number can be interpreted as follows:
1.DAC: Bearing series designation.
2.30: Inner diameter of 30 mm.
3.60: Outer diameter of 60 mm.
4.0037: Bearing width of 37 mm in this designation.
Therefore, its principal dimensions are 30 × 60 × 37 mm.
Another example is DAC34640037, which commonly represents a bearing with a 34 mm inner diameter, 64 mm outer diameter, and 37 mm width.
These examples demonstrate how the numerical sequence can help identify bearing dimensions without immediately consulting a complete technical drawing.
However, some DAC numbers include additional digits, modified dimensional values, or suffixes. Their interpretation may differ from the simplified examples above.
Two DAC bearings may have similar part numbers but different dimensions or internal specifications.
For example, a difference in the outer diameter can prevent a bearing from fitting correctly into the intended housing.
Even when principal dimensions match, variations in sealing arrangements, internal construction, or magnetic encoder features may affect compatibility.
For this reason, DAC part numbers are useful starting points for identification, but a complete technical comparison is still necessary before replacement or bulk purchasing.
Wheel bearing sizes are generally expressed using three measurements: inner diameter (d), outer diameter (D), and width (B). These dimensions are usually specified in millimeters and determine the bearing's basic mounting compatibility.
The inner diameter determines the size of the shaft or hub surface that fits inside the bearing.
The outer diameter determines the required housing or mounting bore. The bearing width describes its axial dimension, which affects how the bearing fits within the wheel assembly.
For example, a bearing specified as 35 × 65 × 35 mm has a 35 mm bore, 65 mm outside diameter, and 35 mm overall width.
Bearing Number | Inner Diameter | Outer Diameter | Width |
|---|---|---|---|
DAC30600037 | 30 mm | 60 mm | 37 mm |
DAC34640037 | 34 mm | 64 mm | 37 mm |
DAC35650035 | 35 mm | 65 mm | 35 mm |
DAC40720037 | 40 mm | 72 mm | 37 mm |
These are representative dimensional designations used to illustrate common DAC bearing sizes. Exact specifications should be confirmed against the relevant product drawing.
Correct dimensions help ensure the bearing fits its intended mounting location.
An incorrect inner diameter can prevent proper installation on the hub or shaft, while an incorrect outer diameter may cause interference or an unsuitable fit within the housing.
Bearing width is equally important because it affects axial positioning and the relationship between surrounding components.
Although dimensional measurements are essential, they do not describe the entire bearing design. Internal geometry, sealing construction, and application requirements must also be considered.
Wheel bearing suffixes may identify sealing arrangements, internal clearance, precision specifications, or design modifications. Their exact meanings depend on the bearing series and the numbering convention being used.
Suffixes appear after the main bearing designation and provide information beyond basic dimensions.
For instance, certain rolling bearing numbering systems use 2RS to indicate rubber seals on both sides and ZZ to indicate metal shields on both sides. However, not every automotive wheel bearing series uses these suffixes in the same way.
Another commonly encountered designation is C3, which indicates an internal clearance range greater than the normal clearance class in applicable standardized bearing systems.
A bearing may have the correct dimensions but an unsuitable sealing or internal clearance specification.
Sealed bearings are commonly used in automotive applications where protection against dirt, moisture, and lubricant loss is important.
Internal clearance also affects how a bearing behaves under mounting and operating conditions. Selecting an unsuitable clearance specification may influence bearing performance.
When comparing replacement bearings, buyers should verify all relevant suffixes rather than assuming that matching main numbers guarantee equivalent products.
For wheel bearings with magnetic encoders, the presence and orientation of the encoder must also be confirmed where applicable.
The most reliable method is to compare the original bearing reference with the replacement part number, dimensional specifications, internal design, and vehicle application information. Matching dimensions alone does not guarantee compatibility.
Begin by identifying the original wheel bearing number. This information may be available on the bearing itself, in the vehicle's parts catalog, or through an established replacement reference.
If the original number cannot be identified, accurate dimensional measurements can help narrow the available options.
However, buyers should not rely solely on measurements when selecting replacement parts.
1.Record the original bearing part number, if available.
2.Confirm the vehicle model, production year, and axle position.
3.Measure or verify the inner diameter, outer diameter, and width.
4.Identify the bearing type and sealing configuration.
5.Check for magnetic encoder or ABS compatibility requirements.
6.Compare the information with the replacement bearing's technical specifications.
These steps help reduce the risk of selecting an incorrect bearing.
Not always.
Two bearings with identical external dimensions may differ in their internal construction, load-supporting characteristics, sealing arrangements, or electronic features.
For example, a wheel bearing designed with a magnetic encoder may not be interchangeable with a similar bearing that lacks the required encoder.
Likewise, differences in installation requirements or internal bearing settings can affect suitability.
A replacement should therefore be confirmed using a reliable application reference and complete technical information.
Wholesale buyers should verify part numbers, dimensions, vehicle applications, bearing construction, and required quantities before placing orders. Accurate specifications help reduce purchasing errors and improve replacement part compatibility.
For automotive parts distributors, wheel bearing numbers are important tools for inventory identification and product sourcing.
Clear product references allow purchasing teams to distinguish between similar bearings and organize inventory according to application requirements.
However, technical descriptions should include more than a single product number. Important details such as dimensions, sealing specifications, and applicable vehicle references can help suppliers confirm the correct product.
When requesting quotations, buyers should provide the required bearing numbers, specifications, order quantities, and any relevant packaging requirements.
If several replacement references appear compatible, technical confirmation should be completed before bulk purchasing.
Maintaining accurate product information also helps distributors respond more efficiently to customer inquiries and reduces confusion between similar wheel bearing models.
Reading wheel bearing part numbers correctly requires understanding the bearing series, dimensional specifications, and any additional identification codes. While DAC series numbers often provide useful dimensional information, complete compatibility verification remains essential.
Inner diameter, outer diameter, and width are the basic measurements used to identify wheel bearings. However, sealing arrangements, internal construction, and vehicle applications can also determine whether a replacement is suitable.
For automotive parts distributors and wholesale buyers, accurate part identification supports efficient sourcing and inventory management.
Explore our automotive wheel bearing range or contact our team with your required part numbers, dimensions, and purchasing quantities to discuss suitable bearing options.
