Chevrolet 1977 light duty truck Service Manual page 363

DIFFERENTIAL A N D REAR AXLE BEARING DIAGNOSIS
A B R A S I V E ROLLER W E A R
PA TTER N ON RACES A N D RO LLERS CAUSED BY
F IN E ABRASIVES.
C LE AN ALL PARTS A N D H OUSINGS. CHECK SEALS
A N D BEA R ING S A N D REPLACE IF LE A K IN G , ROUGH
OR NO ISY.
A B R A S I V E STEP W E A R
P A TTER N ON R O LLER ENDS C AUSED BY
FIN E A BR ASIVES.
CLEAN ALL PARTS A N D HOUSING S. CHECK SEALS
A N D BE ARING S A N D REPLACE IF L E A K IN G , ROUGH
OR N O ISY.
I N D E N T A T I O N S
SURFACE DEPRESSIONS ON RACE A N D ROLLERS
C AUSED BY H A R D PARTICLES OF F O R E IG N M A T E R IA L .
C L E A N A LL PARTS AND H OUSINGS. CHECK SEALS
A N D REPLACE BEARINGS IF ROUGH OR NOISY.
CO NSIDER THE FO LLOW IN G FACTORS W HEN DIA G N O SIN G BEAR IN G C O N D IT IO N :
1. G ENERA L C O N D IT IO N OF A L L PARTS D U R IN G DISASSEM BLY A N D INSPECTION.
2. CLASSIFY THE F A IL U R E W ITH THE A ID OF THE IL L U S T R A T IO N S .
3. DE T E R M IN E TH E CAUSE.
4. M AKE A L L REPAIRS FO LLOW IN G RECOM M END ED PROCEDURES.
G A L L I N G
M ETAL SMEARS ON R OLLER ENDS DUE TO O V E R H E A T ,
LU B R IC A N T F A IL U R E OR O V E R L O A D (WAGON'S)
REPLACE BEARING CHECK SEALS A ND CHECK
FOR PROPER L U B R IC A T IO N .
E T C H I N G
BEAR IN G SURFACES APPEAR G R A Y OR GR A Y IS H
BLACK IN COLOR W ITH R E L A T E D ETCHING AW AY
OF M A T E R IA L U SU A LLY A T RO LLE R SPACING.
REPLACE BEARINGS CHECK SEALS A ND CHECK
FOR PROPER L U B R IC A T IO N .
C A G E W E A R
W EAR A R O U N D O U TSIDE D IA M E T E R OF CAGE A N D
ROLLER POCKETS C AUSED BY A B R A SIV E M A T E R IA L
AND IN E F F IC IE N T L U B R IC A T IO N .
CLEAN R EL A T E D PARTS AND HOUSINGS.
CHECK SEALS AND REPLACE BEARINGS.
BENT CAG E
CAGE D AM AGE DUE TO IMPROPER H A N D L IN G
OR TOOL USAGE.
REPLACE B EA R IN G .
B E N T C A G E
CAGE D A M A G E D U E TO IMPROPER H A N D L IN G
OR TO O L USAGE.
REPLACE B EA RIN G.
M I S A L I G N M E N T
O U T E R RACE M IS A L IG N M E N T DUE TO FO REIGN
OBJECT.
C LE A N R EL A T E D PARTS A N D REPLACE B EA R IN G .
M A K E SURE RACES ARE PROPERLY SEATED.