Chevrolet Light Duty Truck 1973 Service Manual page 264

4 - 4 0 REAR SU SPEN SION AND DRIVELINE
DIFFERENTIAL A N D
C R A C K E D I N N E R
RACE CRACKED DUE TO IMPROPER FIT,
COCKING, OR POOR BEARING SEATS.
REPLACE BEARING A ND CORRECT BEARING
SEATS.
FRETTAGE
CORROSION SET UP BY SM ALL R E LA TIV E
MOVEMENT OF PARTS WITH NO LUBRICATIO N.
REPLACE BEARING . CLEAN R ELATED PARTS.
CHECK SEALS AND CHECK FOR PROPER LUBRICATIO N.
SMEARS
SMEARING OF M E TA L DUE TO SLIPPAGE.
SLIPPAGE CAN BE CAUSED BY POOR FITS.
LU B R IC ATIO N , OVERH EATING , OVERLO ADS
OR H A N D LIN G DAMAGE.
REPLACE BEARINGS, CLEAN R ELATED PARTS
AND CHECK FOR PROPER FITS AND
LUBRICATIO N
REAR AXLE BEARING D IA GNOSIS
(C O N T 'D)
RACE
FATIGUE SPALLING
FLA K IN G OF SURFACE M ETAL RESULTING FROM
FATIGUE.
REPLACE BEARING
STAIN
DISCOLORATION CAN RANGE FROM LIG H T BROWN
TO BLACK CAUSED BY INCORRECT LUB RICAN T OR
MOISTURE.
RE-USE BEARINGS IF STAINS CAN BE REMOVED BY
LIG HT POLISHING OR IF NO EVIDENCE OF O VE R ­
HEATING IS OBSERVED.
CHECK SEALS A ND RELATED PARTS FOR DAMAGE.
Fig. 82—Differential and Axle Bearing Diagnosis Chart B
CLEAN A L L R ELATED PARTS.
D I S C O L O R A T IO N
B R IN ELL ING
SURFACE INDENTATIO NS IN RACEWAY CAUSED BY
ROLLERS EITHER UNDER IMPACT LOADING OR
V IB R A TIO N W HILE THE BEARING IS NOT RO TATING .
REPLACE BEARING IF ROUGH OR NOISY.
HEAT D IS C O L O R A T IO N
HEAT DISCO LO RATIO N CAN RANGE FROM FA INT
YELLOW TO D A R K BLUE RESULTING FROM OVER
LOAD (WAGON'S) OR INCORRECT LUBRICAN T.
EXCESSIVE HEAT CAN CAUSE SOFTENING OF RACES
OR ROLLERS.
TO CHECK FOR LOSS OF TEMPER ON RACES OR
ROLLERS A SIMPLE FILE TEST MAY BE MADE. A
FILE DRAWN OVER A TEMPERED PART W IL L GRAB
AND CUT M E TA L, WHEREAS, A FILE DRAWN OVER A
HARD PART W IL L G LID E R E A D ILY WITH NO M ETAL
CUTTING.
REPLACE BEARING S IF OVER HEATING DAMAGE IS
INDICA TE D. CHECK SEALS A ND OTHER PARTS.
LIGHT DUTY TRUCK SERVICE MANUAL