Buyers’ Guide · Wheel Bearings & Seal Kits

Wheel Bearing & Seal Kits Buyers’ Guide

Wheel bearing and seal kits are sealed hub bearings supplied as complete replacement sets — referenced by ID, height, OD and sealing type across 42 sizes, with OE-style cross-reference support. This guide explains the naming system and how to find the right kit.

Sizes & references: 42
Reference systems: DAC / BEA
Sealing types: 2RS / ZZ / RZ
OE cross-reference: 20-xxxx

SYZ wheel bearing and seal kits — DAC and BEA reference hub bearings — **Plate 1.** SYZ wheel bearing and seal kits — DAC/BEA references across 42 sizes and sealing types. Source: Wheel bearing spec page

What Are Wheel Bearing & Seal Kits?

Definition

A wheel bearing and seal kit is the complete sealed hub bearing — typically a DAC (double-row angular contact) unit — supplied as a replacement set with its seals. These bearings carry the vehicle’s weight and wheel rotation loads at the hub, sealed for life or serviceable by seal type.

Sizing is a four-number system: ID (bore) × height × OD, plus the sealing type (2RS double rubber seals, ZZ metal shields, RZ single-lip variants). SYZ covers 42 sizes and references across DAC and BEA systems, with OE-style cross-reference support (the 20-xxxx service numbers) — send your old part number or the measured dimensions for a match.

Also called: Hub bearing kits · DAC bearings
Core function: Sealed hub rotation under vehicle load
Dimension system: ID × height × OD × sealing
Cross-reference: OE-style 20-xxxx support

Anatomy: The Four-Number System

Structure

Every kit is identified by four attributes — reading them is the selection.

2.1

ID — Inner Bore

The bore that fits the hub spindle or axle, in millimeters with tight negative tolerance (e.g., 40 -0.013). The first dimension to measure.

2.2

Height (Width)

The bearing’s assembled width — the second matching dimension for the hub pocket.

2.3

OD — Outer Diameter

The outside diameter that press-fits into the hub housing — again tightly toleranced for the press fit.

2.4

Sealing Type

2RS = double rubber seals (default), ZZ = metal shields, RZ/2RZ = single-lip variants — the choice decides contamination and moisture resistance.

2RS — Double Rubber Seals

Default sealing

Double rubber contact seals — the best protection against water, mud and dust for exposed hubs on ATVs, UTVs, trailers and light vehicles.

The default choice across the catalog.

Series — DAC 2RS kits

ZZ / RZ — Shielded & Single-Lip

Speed & specific fit

Metal shields (ZZ) for lower friction where contamination is mild; single-lip RZ variants where the OE specification calls for them.

Follow the OE sealing type when cross-referencing — the seal is part of the fit.

Series — DAC ZZ / RZ kits

What a Wheel Bearing Kit Does at the Hub

Function

Four engineering jobs — each maps to a selection check.

3.1

Carry vehicle load rotating

The double-row angular contact design carries radial and axial loads simultaneously at the hub — sized by the vehicle’s corner weights.

3.2

Rotate sealed

The integrated seals keep grease in and contamination out — the sealing type decides how well that holds in mud and washdown.

3.3

Press-fit into the hub

Both ID and OD are precision press fits — dimensions are matched to the spindle and housing, which is why the four numbers must be exact.

3.4

Cross-reference cleanly

The 20-xxxx OE-style numbers map to the original service part — send the old number or the four measured dimensions for a match.

Where wheel bearing replacements fail

Guessing dimensions instead of measuring ID, height, OD precisely.
Substituting sealing types against the OE specification.
Hammering instead of pressing — brinelling the bearing.
Ignoring the seals during install — a nicked 2RS seal leaks early.

Construction and Sealing

Materials

Hub bearings are sealed bearing-steel units; the seal type is the service decision.

DAC 2RS wheel bearing kits with rubber seals

2RS Double Seals

Default protection

Double rubber contact seals — the mud, water and dust protection default for exposed hubs.

Best for ATV, UTV, trailer hubsExplore 2RS kits →

ZZ / RZ Options

OE-specified sealing

Metal shields and single-lip variants where the OE specification calls for them — follow the original part.

Best for OE-specified fitsExplore ZZ/RZ →

OE Cross-Reference

20-xxxx service numbers

Send your old service number (20-xxxx) or the measured dimensions — SYZ cross-references to the matching kit.

Best for Match by part numberExplore cross-reference →

Construction and Sealing

Surface treatment

The bearing is sealed steel — the choice is the seal.

Treatment	Applied to	Series examples	What it does
Bearing steel, sealed unit	Bearing assembly	All 42 sizes	Double-row angular contact unit, grease-packed and sealed.
2RS rubber seals	Both faces	Default kits	Best contamination and moisture protection for exposed hubs.
ZZ metal shields	Both faces	Selected kits	Lower-friction shielding where the OE spec calls for it.
RZ / 2RZ seals	Single-lip variants	Selected kits	OE-specified single-lip sealing.

The full 42-size reference chart (model, part, ID, height, OD, sealing) is on the wheel bearing spec page.

Where Wheel Bearing Kits Perform

Applications

Replacement hub bearings across light vehicles and equipment.

ATV & UTV Hubs

Sealed hub kits for off-road machines — 2RS sealing against mud and water.

2RS kits

Trailers & Light Vehicles

Hub bearing replacement by measured dimensions or OE number.

DAC kits

Golf Carts & Equipment

Sealed hub bearings for light electric and utility vehicles.

DAC kits

Cross-Reference Service

OE-style 20-xxxx numbers matched to SYZ kits for service programs.

Cross-ref

How to Choose: 4 Steps, Then the Reference Chart

Selection reference

Measure the Four Numbers

ID, height and OD in millimeters (precision-measured), plus the sealing type on the old unit.

Or Send the Part Number

The 20-xxxx OE-style number or the original bearing marking — SYZ cross-references it.

Confirm the Sealing

2RS unless the OE specifies ZZ/RZ — the seal type is part of the fit.

Press, Don’t Hammer

Install with proper press tooling; protect the seals during the job.

Attribute	Specification	Notes	Specs
Wheel bearing & seal kits
Reference systems	DAC / BEA + OE-style 20-xxxx	42 sizes & references	View
Dimension system	ID × height × OD × sealing	Precision-measured match	View
Sealing types	2RS · ZZ · RZ / 2RZ	2RS is the default	View
Support	Cross-reference service	By part number or dimensions	View

Other sealed joints on the machine? See spherical plain bearings for pivots and rod ends for linkage.

Get Selection Help

Wheel Bearing Buyers’ Questions

FAQ

Q1What does the DAC designation mean?

DAC refers to the double-row angular contact hub bearing construction — the standard sealed unit for wheel hubs. BEA references cover the alternate system in the catalog.

Q2How do I identify the right kit?

Measure ID, height and OD in millimeters, and note the sealing type (2RS, ZZ, RZ). Or send the OE-style 20-xxxx service number for cross-reference.

Q3What is the difference between 2RS and ZZ?

2RS is double rubber contact seals — the best protection against water and mud. ZZ is metal shields — lower friction, for milder contamination. Follow the OE specification.

Q4What sizes are covered?

42 sizes and references — the chart on the spec page lists model, part number, ID, height, OD and sealing for each.

Q5Do the kits include seals?

Yes — these are bearing and seal kits: the sealed bearing unit with its seals as a complete replacement set.

Need adjacent catalog coverage? See All Products for the wider component catalog while using this guide to match wheel-bearing and seal kits by dimensions or service number.

Selecting Wheel Bearing & Seal Kits?

Send us the old part number or your measured ID/height/OD and sealing type — SYZ cross-references the kit and replies with factory-direct pricing.

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