Engineering Analysis · LOWER CONTROL ARM · Opened 1987-11-06 · Closed 1988-10-24
Investigation
Action number
EA88007
Type
Engineering Analysis
Open date
1987-11-06
Close date
1988-10-24
Manufacturer
General Motors, LLC
Affected makes
CHEVROLET; GMC
Affected components
SUSPENSION
Affected model years
1984, 1985, 1986, 1987
Affected (make, year) variants
56
Summary
SUMMARY OF INFORMATION FROM MANUFACTURER:MANUFACTURER IS IN RECEIPT OFONE COMPLAINT AND FIVE FIELD REPORTS.PRODUCT REPORT ANALYSIS STATES THELOWER CONTROL ARM FROM WAGGONER CORPORATION APPEARS TO HAVE A SMALL RADIUSAT THE TRANSITION OF THE SIDE WALL TO THE BALL STUD NOSE.CURRENT STAMPINGSOURCE, S.K.D., ALSO HAS A SMALL RADIUS IN THE SAME AREA.S.K.D. HASCHANGED THE TRIM TO INCREASE THE RADIUS TO 1 INCH AND PROVIDE ADDITIONALSTRENGTH IN THE BALL STUD AREA.ANALYSIS:FAILURE DATA INDICATES THE LEFT CONTROL ARM AND DIESEL ENGINEAPPLICATION ARE OVER REPRESENTED.ALL KNOWN FAILURES HAVE OCCURRED AT LOWSPEEDS, OR HAVE BEEN LOCATED AS A RESULT OF AN INCREASE IN THE FREQUENCY OFMAINTENANCE INSPECTIONS.BALL JOINT SEPARATION COULD RESULT IN COLLAPSE OFFRONT WHEEL SUSPENSION AND LOSS OF VEHICLE CONTROL.ACTION: IR TO GM SENT 11/19/87 CONTACT FLEET OWNERS.===