SUMMARY:GM IS CONDUCTING A VOLUNTARY RECALL CAMPAIGN (85V-048)INVOLVING 2,136,826 VEHICLES. THE RECALL IS LIMITED TO VEHICLES BUILT ATCERTAIN ASSEMBLY PLANTS WHICH, ACCORDING TO GM, OVERTORQUED THE BRAKEPIPE NUT,THEREBY OVERSTRESSING THE WHEEL CYLINDER SUPPORT AREA OF THEBACKING PLATE.ANALYSIS:FRONT BRAKES PROVIDE SUFFICIENT BRAKING FOR PASSENGER CARSIN MOST NON-EMERGENCY SITUATIONS. ALL AFFECTED TRUCKS ARE INCLUDED INTHE CURRENT RECALL.IN MOST CASES THE PROBLEM IS DISCOVERED DURING BRAKEMAINTENANCE.THE RECALL APPEARS TO COVER THOSE GROUPS OF CARS WITH THEHIGHEST FAILURE RATES.STATUS:ANALYZING GM IR RESPONSE AND NEW COMPLAINT DATA. DRAFT CLOSINGREPORT BY 5/15/88.===