GMC 1982 Light Duty Truck Service Manual page 425

DIFFERENTIAL A N D REAR AXLE BEARING DIAGNOSIS
A B R A S I V E ROLLER W E A R
P AT T ER N ON RACES A N D R O LLE R S CAU SED BY
FINE A B R AS IVES .
C LE A N A L L PARTS A N D HOUSINGS. CHECK SEALS
A N D BE AR IN G S A N D REPLACE IF L E A K IN G . ROUGH
OR NO IS Y .
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A B R A S I V E STEP W E A R
PA TT E R N ON R O LLE R ENDS C AUSED BY
FIN E A B R ASIVE S.
C LE A N A L L PARTS A N D HOUSINGS. CHEC K SEALS
A N D B E A R IN G S A N D REPLACE IF L E A K IN G , ROUGH
OR NOISY.
I N D E NT A T I O N S
SURFACE DEPRESSIONS ON RACE A N D R O LLER S
CAUSED BY H A R D PAR TIC LES OF FO R EIG N M A T E R IA L .
C LE A N A L L PARTS A N D HOUSINGS. C HECK SEALS
A N D REPLACE BE AR IN G S IF ROUGH OR N OISY.
CO NSIDER THE F O LLO W IN G FACTORS WHEN DIAG N O SIN G B EAR IN G C O N D IT IO N :
1. G E N E R A L C O N D IT IO N OF A L L PARTS D U R IN G D ISASSEM BLY A N D INSPECTION
2. C LA S S IF Y THE F A IL U R E W ITH THE A ID OF THE ILLU S T R A T IO N S .
3. D ETE R M IN E TH E CAUSE.
4 M A K E A L L REPAIRS FO LLO W IN G R EC O M M EN D ED PROCEDURES.
G A L L I N G
M E T A L SM EARS ON R O LLE R 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 L O A D (W AGON'S)
REPLACE B E A R IN G CHECK SEALS A N D CHECK
FOR PROPER L U B R IC A T IO N .
E TC HI NG
BE A R IN G SURFACES APPEAR G R A Y OR G R A Y IS H
BLA C K IN CO LO R W ITH R E L A T E D ETCHING AW AY
OF M A T E R IA L U S U A L L Y AT R O LLE R SPACING.
REPLACE B EA R IN G S CHECK SEALS A N D CHECK
FOR PROPER L U B R IC A T IO N .
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C A G E W E A R
W EAR A R O U N D O U TS ID E D IA M E T E R OF CAGE A N D
R O LLE R POCKETS CAUSED BY A B R A S IV E M A T E R IA L
A N D IN E F F IC IE N T LU B R IC A T IO N .
C LE A N R E LA T E D PARTS A N D HOUSINGS.
CHECK SEALS A N D REPLAC E BEAR IN G S.
Keyliner-Differential and Axle Bearing Diagnosis Chart A
REAR A X L E
BENT C A G E
CAGE D A M A G E DUE TO IM PROPER H A N D L IN G
OR TO O L USAGE.
REPLACE B EAR IN G .
B E N T C A G E
CAGE D A M A G E DUE TO IMPROPER H A N D L IN G
OR TO O L USAGE.
REPLACE BE A R IN G .
M I S A L I G N M E N T
O UTER RACE M IS A LIG N M E N T DUE TO FO REIG N
OBJECT.
C LE A N R E LA T E D PARTS A N D REPLACE BEAR IN G .
M A K E SURE RACES AR E PROPERLY SEATED.
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