GMC M9500 1977: WHEELS:HUB
NHTSA Campaign ID Number: 77V172000
| Make | Model | Year |
|---|---|---|
| GMC | M9500 | 1977 |
| Date Owners Notified | Date Received by ODI | Date Added to Database |
| 1977-10-31 | 1977-10-12 | 1979-10-12 |
Production Dates: 1976-03-01 - 1977-06-01
Manufacturers Involved: General Motors, LLC
Component: WHEELS:HUB
Potential Number Of Units Affected: 685
Report Initiator: MFR MFR Report
THE FRONT AXLE ALUMINUM HUBS ON THE INVOLVED VEHICLES MAY CONTAIN A DEFICIENCY IN THE BARREL AREA BETWEEN THE INNER AND OUTER BEARINGS WHICH MAY RESULT IN CRACKS WHICH COULD EVENTUALLY LEAD TO HUB FAILURE.
DEALER WILL INSPECT AND REPLACE FRONT AXLE ALUMINUM HUBS WITH STEEL HUBS, WITHOUT CHARGE TO OWNER.
VEHICLE DESCRIPTION: HEAVY TRUCKS EQUIPPED WITH FF931 FRONT AXLES AND MOTORWHEEL ALUMINUM FRONT HUBS.SYSTEM: WHEELS; ALUMINUM HUBS.CONSEQUENCES OF DEFECT: WHEN HUB FAILURE OCCURS, THE SEPARATED HUB IS RETAINEDON THE AXLE SPINDLE BY THE WHEEL BEARING ADJUSTING NUTS. CONTINUED VEHICLEOPERATION AFTER A HUB SEPARATION CAN RESULT IN 1' BRAKE ASSEMBLY LOCKUP ANDCONSEQUENT LOSS OF VEHICLE CONTROL, 2' EXCESSIVE HEAT GENERATION RESULTING FROMTHE BRAKE LINE TOUCHING THE BRAKE DRUM WHICH WILL CAUSE A TIRE BLOWOUT AND 3'PROGRESSIVE DAMAGE TO THE HUB WHICH WOULD ALLOW THE HUB, WHEEL, AND TIRE TOBECOME DISENGAGED FROM THE VEHICLE.NOTE: INITIAL HUB SEPARATION MAY BE ACCOMPANIED BY A DISTINCT SOUND AT THEMOMENT OF SEPARATION, ALONG WITH THUMPING OR WHEEL WOBBLE.
