Chevrolet 1980 Light Duty Truck Service Manual page 337

DIFFERENTIAL AND REAR A X LE BEARING DIAGNOSIS
ABRASIVE ROLLER WEAR
P A TTE R N ON RACES A ND RO LLER S CAUSED BY
F IN E ABRASIVES.
C LE A N A L L PARTS A N D HOUSINGS. CHECK SEALS
A N D B EA RING S A ND REPLACE IF L EA K IN G , ROUGH
OR NO IS Y.
f t *
ABRASIVE STEP WEAR
P ATTE RN ON RO LLER ENDS CAUSED BY
FINE ABRASIVES.
C LEAN A LL PARTS A N D HOUSINGS. CHECK SEALS
A N D BEARINGS AN D REPLACE IF L E A K IN G . ROUGH
OR NO ISY.
INDENTATIONS
SURFACE DEPRESSIONS ON RACE A N D ROLLERS
CAUSED BY H A R D PARTICLES OF FO R EIG N M A T E R IA L .
CLEAN A LL PARTS AND HOUSINGS. CHECK SEALS
A N D REPLACE B EAR ING S IF ROUGH OR NO ISY.
CO NSIDER THE FOLLO W IN G FACTORS W HEN D IA G N O S IN G B EA R IN G C O N D ITIO N :
1. G EN ER AL C O N D IT IO N OF A LL PARTS D U R IN G DISASSEM BLY A ND INSPECTION.
2. C LA SSIFY TH E F A IL U R E W ITH THE A ID OF TH E IL LU S T R A TIO N S .
3. D E T E R M IN E TH E CAUSE.
4. M A K E A LL REPAIRS FOLLO W IN G R EC O M M EN D ED PROCEDURES.
GALLING
M ETA L SMEARS ON RO LLER ENDS DUE TO O V E R H E A T,
L U B R IC A N T F A IL U R E OR O V E R LO A D (WAGON'S)
REPLACE B EA R IN G - CHECK SEALS A N D CHECK
FOR PROPER L U B R IC A T IO N .
ETCHING
BEA R IN G SURFACES APPEAR G R A Y OR G R A Y IS H
BLACK IN COLOR W ITH R E L A T E D ETC H IN G AW AY
OF M A T E R IA L U S U A L L Y A T RO LLER SPACING.
REPLACE B E ARINGS CHECK SEALS A N D CHECK
FOR PROPER LU B R IC A T IO N .
CAGE WEAR
WEAR A R O U N D OU TS ID E D IA M E T E R OF CAGE A ND
RO LLER POCKETS CAUSED BY A B R A S IV E M A TE R IA L
A N D IN E F F IC IE N T L U B R IC A T IO N .
C LEA N R E L A T E D PARTS A N D HOUSINGS.
CHECK SEALS A N D REPLACE BEARINGS.
Fig. 4B-1 2--Differential and Axle Bearing Diagnosis Chart A
REAR AXLE
BENT CAGE
CAGE D A M A GE DUE TO IMPROPER H A N D L IN G
OR TOOL USAGE.
REPLACE B EA R IN G .
BENT CAGE
CAGE D A M A G E D U E TO IMPROPER H A N D L IN G
OR TO OL USAGE
MISALIGNMENT
OU TER RACE M IS A L IG N M E N T DUE TO FO R EIG N
OBJECT.
CLEAN R E L A TE D PARTS A N D REPLACE B E A R IN G .
M A K E SURE RACES ARE PROPERLY SEATED.
L IG H T T R U C K SER V IC E M AN UAL
4 B -1 1