KIC Catalog

Wheel Seal and Bearing Removal, Installation & Maintenance

PREFACE

The following Recommended Practice is subject to the

Disclaimer at the front of TMC’s

Recommended Main-

tenance Practices Manual

. Users are urged to read the

Disclaimer before considering adoption of any portion of

this Recommended Practice.

PURPOSE AND SCOPE

This Recommended Practice defines practices and pro-

cedures to perform a wheel seal replacement that meets

fleet requirements. This Recommended Practice sets

forth procedures and standards for storage, handling,

and installation of wheel seals and wheel bearings for

heavy-duty vehicles.

INTRODUCTION

Awheel seal is comprised of as many as six components,

each manufactured to within a tolerance of a few thou-

sandths of an inch. These components are assembled in

precision fixtures, packed, and delivered ready for use.

A wheel seal is a precision component, expected to do a

demanding job. How it performs depends largely on the

conditions of the seven mating wheel end components

and the care taken during installation.

WHEEL SEAL AND BEARING HANDLING AND

STORAGE

Many wheel seal failures can be traced to improper han-

dling and/or storage of the seals or bearings prior to use.

Seals and bearings must be handled with care.

1. Wheel seals should be kept away from electric

motors, welding equipment, and all other sourc-

es of ozone. Fluorescent light and direct sunlight

are also destructive to wheel seals.

2. Store wheel seals and wheel bearings in a clean,

dry place. They should not be exposed to ex-

tremes of either dryness or dampness.

3. Wheel seals and wheel bearings should be kept

in their original factory packaging until ready for

installation. Never store wheel seals or wheel

bearings unprotected in open bins, where they

may be exposed to airborne contaminants.

4. Never hang wheel seals and bearings on hooks

or nails. Never tag wheel seals or bearings with

inventory tags by looping wire through the seal

or bearing. These practices will damage the deli-

cate seal lip, the rubber inside diameter (I.D.) or

outside diameter (O.D.) of the seal, or precision

machined bearing surfaces.

Keep wheel seals and bearings clean—Never lay wheel

seals and bearings on a dirty surface and wash your

hands prior to handling them. Avoid dropping oil seals

and bearings. This will cause internal damage which

may not be visibly apparent, but may be sufficient to im-

pair their efficiency. Seals or bearings which have been

dropped should be replaced.

NOTE:

Never rotate an unlubricated wheel bearing or

spin it with an air gun.

WHEEL SEAL AND BEARING REMOVAL AND

DISASSEMBLY

Wheel Seal Removal

—A pry-bar is recommended for

removal of the seal from the hub bore. A spindlemount

wheel seal can be driven off the spindle by striking the

ring from the back side or prying off with a crow’s foot

bar. If a flat wear sleeve is on the spindle, remove it by

striking the sleeve face with the round end of a ball peen

hammer, expanding it for easy removal. Never use a

sharp tool or chisel to remove the sleeve, because this

will damage the shoulder area of the spindle. Discard

the used wheel seal and use a new one during reas-

sembly.

Bearing Cup Removal: Ferrous Hubs

—Removal of

bearings and cups should be done with extreme care so

that hub bores, bearings, spindles, and housings are not

damaged. Follow the hub manufacturer’s procedures for

removing the bearing cups. This can best be done by

using a bearing puller or press. When pullers or presses

are not available for cup removal, a soft steel bar may

be used. Do not use hardened drifts, center punches, or

brass bars. They may chip and cause damage or per-

sonal injury.

Bearing Cup Removal: Aluminum Hubs

—Removal of

bearings and cups should be done with extreme care so

that hub bores, bearings, spindles, and housings are not

damaged. Follow the hub manufacturer’s procedures for

removing the bearing cups. To remove the cups, heat

the hub to 250 - 300° F (120 - 150°C) in an oven. Do not

exceed 300° F (150°C). Higher temperatures may weak-

en the hub material. Do not use acetylene torches or

other welding equipment to heat the hub because local-

ized high temperatures may result, weakening the hub.

Allow enough time in the oven for the hub to reach a uni-

form temperature. Hub temperatures can be measured

by using a temperature probe such as a thermocouple

or temperature sensitive wax markers which are widely

available from temperature measuring equipment sup-

pliers. Use the appropriate safety equipment when han-

dling the hot hub to avoid burns. Next, place the heated

hub in a press and press the cup out.

Cleaning Wheel Bearings

—A bearing which has been