CAMPAIGN:BRAKE PUSH ROD DISENGAGEMENT

DEALER PRODUCT CAMPAIGN BULLETIN GMC NUMBER: 93-C-17 GROUP: 5-BRAKES

DATE: OCTOBER 1993

SUBJECT: BRAKE PEDAL PUSH ROD DISENGAGEMENT

MODELS: 1993 B7 SCHOOL BUS CHASSIS WITH HYDRAULIC BRAKES (JE3)

THE NATIONAL TRAFFIC AND MOTOR VEHICLE SAFETY ACT, AS AMENDED, PROVIDES THAT EACH VEHICLE WHICH IS SUBJECT TO A RECALL CAMPAIGN OF THIS TYPE MUST BE ADEQUATELY REPAIRED WITHIN A REASONABLE TIME AFTER THE OWNER HAS TENDERED IT FOR REPAIR. A FAILURE TO ADEQUATELY REPAIR WITHIN 60 DAYS AFTER TENDER OF A VEHICLE IS PRIMA FACIE EVIDENCE OF FAILURE TO REPAIR WITHIN A REASONABLE TIME.

IF THE CONDITION IS NOT ADEQUATELY REPAIRED WITHIN A REASONABLE TIME, THE OWNER MAY BE ENTITLED TO AN IDENTICAL OR REASONABLY EQUIVALENT VEHICLE AT NO CHARGE, OR TO A REFUND OF THE PURCHASE PRICE LESS A REASONABLE ALLOWANCE FOR DEPRECIATION.

TO AVOID HAVING TO PROVIDE THESE BURDENSOME SOLUTIONS, EVERY EFFORT MUST BE MADE TO PROMPTLY SCHEDULE APPOINTMENTS WITH OWNERS AND TO REPAIR THEIR VEHICLES AS SOON AS POSSIBLE. AS YOU WILL SEE IN READING THE ATTACHED COPY OF THE LETTER WHICH IS BEING SENT TO OWNERS, THE OWNER IS BEING INSTRUCTED TO CONTACT THE GMC TRUCK DIVISION CONSUMER RELATIONS OFFICE IF THE DEALER DOES NOT REMEDY THE CONDITION WITHIN FIVE DAYS OF THE MUTUALLY AGREED UPON SERVICE DATE. IF THE CONDITION IS NOT REMEDIED WITHIN A REASONABLE TIME, THEY ARE INSTRUCTED HOW TO CONTACT THE NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION.

DEFECT INVOLVED

GENERAL MOTORS HAS DETERMINED THAT A DEFECT, WHICH RELATES TO MOTOR VEHICLE SAFETY, EXISTS IN CERTAIN 1993 GMC TRUCK OR CHEVROLET B7 SCHOOL BUS CHASSIS EQUIPPED WITH HYDRAULIC BRAKES. A CONDITION EXISTS WHERE THE BRAKE PEDAL PUSH ROD COULD BECOME DISENGAGED FROM THE BRAKE BOOSTER RESULTING IN LOSS OF BRAKING CAPABILITY. ALTHOUGH THE BUS CAN STILL BE STOPPED WITH THE PARK BRAKE, LOSS OF SERVICE BRAKES AT A TIME WHEN MINIMUM STOPPING DISTANCE IS REQUIRED COULD RESULT IN A VEHICLE CRASH WITHOUT PRIOR WARNING.

VEHICLES INVOLVED

INVOLVED ARE CERTAIN 1993 B7 MEDIUM DUTY SCHOOL BUS CHASSIS BUILT WITH HYDRAULIC BRAKES (JE3) WITHIN THE FOLLOWING VIN BREAKPOINTS:

YEAR/MODEL FROM TO

1993 GMC TRUCK B7 JANESVILLE PJ650001 PJ650221 1993 GMC TRUCK B7 JANESVILLE PJ500008 PJ512886 1993 CHEVROLET B7 JANESVILLE PJ610051 PJ610230 1993 CHEVROLET B7 JANESVILLE PJ100016 PJ107195

THE SPECIFIC VEHICLES INVOLVED IN THIS CAMPAIGN HAVE BEEN IDENTIFIED BY VEHICLE IDENTIFICATION NUMBER (VIN) COMPUTER LISTINGS. THESE LISTINGS ARE FURNISHED TO ALL INVOLVED DEALERS WITH THE CAMPAIGN.

DEALER CAMPAIGN RESPONSIBILITY

DEALERS ARE TO SERVICE ALL VEHICLES SUBJECT TO THIS CAMPAIGN AT NO CHARGE TO OWNERS, REGARDLESS OF MILEAGE, AGE OF VEHICLE, OR OWNERSHIP, FROM THIS TIME FORWARD. DEALERS ARE TO INSPECT AND CORRECT ALL AFFECTED VEHICLES IN NEW AND USED VEHICLE STOCK PRIOR TO THEIR SALE.

WHENEVER A VEHICLE SUBJECT TO THIS CAMPAIGN IS TAKEN INTO YOUR NEW OR USED VEHICLE INVENTORY, OR IS IN YOUR DEALERSHIP FOR SERVICE IN THE FUTURE, YOU SHOULD TAKE THE STEPS NECESSARY TO ENSURE THE CAMPAIGN CORRECTION HAS BEEN MADE BEFORE RESELLING OR RELEASING THE VEHICLE.

OWNERS OF VEHICLES RECENTLY SOLD FROM YOUR NEW VEHICLE INVENTORY ARE TO BE CONTACTED BY THE DEALER AND ARRANGEMENTS MADE TO MAKE THE REQUIRED CORRECTION ACCORDING TO INSTRUCTIONS CONTAINED IN THIS BULLETIN.

IF THE NAME AND ADDRESS OF THE OWNER OF AN INVOLVED VEHICLE WAS UNAVAILABLE TO GMC TRUCK DIVISION AT THE TIME OF CAMPAIGN INITIATION, THE DEALER MUST DETERMINE THE OWNER'S NAME AND ADDRESS FROM THE DEALERSHIP SALES RECORDS. PLEASE PROVIDE THIS INFORMATION DIRECTLY ON THE SECOND COPY OF THE LISTING NEXT TO THE APPLICABLE VIN SO THAT OUR RECORDS MAY BE UPDATED AND THE APPROPRIATE NOTIFICATION MAILED TO THE OWNER. THIS SECOND COPY SHOULD THEN BE SUBMITTED TO THE FOLLOWING ADDRESS IN THE PREVIOUSLY SUPPLIED YELLOW CAMPAIGN ENVELOPES.

GMC TRUCK DIVISION GENERAL MOTORS CORPORATION 101 UNION STREET PLYMOUTH, MICHIGAN 48170

OWNER NOTIFICATION

OWNERS WILL BE NOTIFIED OF THIS CAMPAIGN ON THEIR VEHICLES BY GMC TRUCK DIVISION (SEE COPY OF OWNER LETTER INCLUDED WITH THIS BULLETIN). A LISTING OF OWNER NAMES AND ADDRESSES HAS BEEN FURNISHED TO THE INVOLVED DEALERS TO ENABLE DEALERS TO FOLLOW UP WITH OWNERS INVOLVED IN THIS CAMPAIGN. THIS LISTING MAY CONTAIN OWNER NAMES AND ADDRESSES OBTAINED FROM STATE MOTOR VEHICLE REGISTRATION RECORDS. THE USE OF SUCH MOTOR VEHICLE REGISTRATION DATA FOR ANY OTHER PURPOSE IS A VIOLATION OF LAW IN SEVERAL STATES. ACCORDINGLY, YOU ARE URGED TO LIMIT THE USE OF THIS LISTING TO THIS CAMPAIGN.

SERVICE PROCEDURE

INSPECTION FOR MISPOSITIONED OR BROKEN PUSH ROD RETAINER

1.INSPECT BRAKE PEDAL FOR EXCESSIVE TRAVEL. BY HAND, PULL THE BRAKE PEDAL BACK TOWARDS THE DRIVERS SEAT WITH NOT MORE THAN 20 LBS OF FORCE. IF PEDAL MOVES IN EXCESS OF 6 MM (ABOUT 1/4 INCH) FROM ITS STATIC POSITION, THE PUSH ROD RETAINER CLIP MAY BE MISPOSITIONED OR BROKEN (SEE FIGURE 1).

2.SYMPTOMS OF THIS CONDITION MAY BE:

A.) BRAKE LIGHTS STAY ON AND AUXILIARY BOOSTER PUMP MOTOR RUNS CONTINUOUSLY WITH THE ENGINE NOT RUNNING. B.) STOP LAMP SWITCH DAMAGE OR CONTINUOUS ADJUSTMENT PROBLEMS. C.) BRAKE PEDAL BOUNCING EXCESSIVELY WHILE DRIVING DOWN THE ROAD.

3.IF THESE SYMPTOMS ARE VERIFIED, IT WILL BE NECESSARY TO REMOVE THE BOOSTER ASSEMBLY AND REPLACE THE RETAINER CLIP (PART NUMBER 18020694 REFER TO SERVICE MANUAL SECTION 5D2 HYDRAULIC BOOSTER SYSTEM.

IMPORTANT: ALL VEHICLES WILL NOT REQUIRE A RETAINER CLIP REPLACEMEN

INSTALLATION OF BRAKE PEDAL RETURN STOP

1. DISCONNECT BATTERY.

2. PULL FLOOR MAT AND FLAMMABLE MATERIAL AWAY FROM THE WELDIN AREA NEAR LOWER STEERING COLUMN TO IP DASH ATTACHMENT.

3. STEERING COLUMN CAN BE LOWERED TO ALLOW BETTER ACCESS TO T REWORK AREA (SEE FIGURE 2):

A.DISCONNECT THE ELECTRICAL CONNECTIONS ON THE STEERING COLUMN. B.REMOVE UPPER 2 NUTS (ITEM NUMBER 1) AND OVAL WASHERS. C.REMOVE LOWER STEERING COLUMN BOLTS AND NUT (ITEMS NUMBER 2 & 3) D.GENTLY LAY STEERING COLUMN DOWN.

4. PLACE NEW STOP BRACKET IN POSITION (SEE FIGURE 2, VIEW A) AND CHECK FIT. NOTE CLEARANCE TO BACK OF BRAKE PEDAL BRACKET, IT SHOULD BE A MINIMUM OF 2 MM (ABOUT 1/16 INCH).

5. WIRE BRUSH/FILE AREA TO BE WELDED ON PEDAL BRACKET. CLAMP NEW STOP BRACKET IN POSITION (NEEDLE NOSE VISE GRIPS WORK BEST).

6. DISCONNECT STOP LAMP SWITCH CONNECTOR AND REMOVE STOP LAMP SWITCH TO PROTECT FROM HEAT.

7. WELD NEW STOP BRACKET IN POSITION WITH WELDS AT EACH END. (THE WELD AREA IS MARKED ON FIGURE 2, VIEW A WITH "XXX"). WELD SPECIFICATIONS ARE 3.0 V 15.0 ~(WA, WHICH ACCORDING TO AMERICAN WELDING SOCIETY IS A WELD OF 3 MM THICKNESS (ABOUT 1/8 INCH THICK) B 15 MM LENGTH (ABOUT 1/2 INCH LONG), USING A 70 SERIES STEEL ELECTROD

8. CHECK STRENGTH OF COMPLETED WELDING BY PLACING A 1/4 INCH THICK, SOLID METAL OBJECT OR BAR BETWEEN THE STOP AND THE BRAKE PEDA (THIS 1/4 INCH OBJECT SHOULD NOT DEFORM IN ANY WAY UNDER PRESSURE). THEN PULL THE BRAKE PEDAL BACK TOWARDS THE DRIVERS SEAT WITH APPROXIMATELY 100 LBS. OF FORCE. THE STOP BRACKET SHOULD REMAIN FIRMLY IN POSITION WITHOUT BENDING OR COMING LOOSE. REMOVE THE 1/4 INCH THICK METAL OBJECT.

9. REPLACE STOP LAMP SWITCH AND RE-ADJUST PER SERVICE MANUAL, SECTION 5 HYDRAULIC BRAKES.

10. RE-INSTALL STEERING COLUMN AND RE-TORQUE ALL FASTENERS (IT NUMBER 1 TO 30-35 LBS.-FT, ITEMS 2 AND 3 TO 8-10 LBS.-FT).

11. RE-CONNECT ALL CONNECTORS AND CHECK FUNCTIONS.

IMPORTANT: ALL CAMPAIGN OR SUBJECT VEHICLES WILL REQUIRE WELDING OF A RETURN STOP, EVEN IF THEY DO NOT NEED A RETAINER CLIP REPLACEMENT.

PARTS INFORMATION

PARTS ARE TO BE OBTAINED FROM GENERAL MOTORS SERVICE PARTS OPERATION (GMSPO). PARTS WILL BE AVAILABLE FOR SHIPMENT FROM GMSPO ON 10/18/93. TO ENSURE THAT THESE PARTS WILL BE OBTAINED AS SOON AS POSSIBLE, THEY SHOULD BE ORDERED FROM GMSPO ON A C.I.O. ORDER WITH NO SPECIAL INSTRUCTION CODE BUT ORDER UNDER AN ADVISE CODE (2).

PART NUMBER DESCRIPTION QUANTITY 15988148 BRAKE PEDAL STOP 1 BRACKET 18020694 RETAINER CLIP (IF 1 NECESSARY)

WARRANTY INFORMATION

DEALERS SHOULD SUBMIT AN ACCURATELY FILLED OUT WARRANTY REPAIR ORDER O EACH VEHICLE COMPLETED UNDER THIS CAMPAIGN.

LABOR DESCRIPTION *TIME TROUBLE PARTS OPERATION ALLOWANCE CODE ALLOWANC NUMBER E

V8340 INSPECT PUSH ROD 0.5 HR. 96 ** TRAVEL AND WELD RETURN STOP V8341 INSPECT PUSH ROD 1.9 HR. 96 ** TRAVEL, WELD RETURN STOP, AND REPLACE RETAINER CLIP

* FOR DEALER TO RECEIVE ADMINISTRATIVE TIME ALLOWANCE ASSOCIATED WITH THIS CAMPAIGN, ADD 0.1 HOUR TO THE LABOR OPERATION TIME ALLOWANCE.

** THE AMOUNT IDENTIFIED IN THE "PARTS ALLOWANCE" COLUMN ABOVE REPRESENTS 30% OF DEALER NET FOR PARTS THAT ARE FURNISHED IN THIS CAMPAIGN. THIS AMOUNT IS TO BE PLACED IN THE NET ITEM AMOUNT COLUMN O THE CLAIM AND TYPE CODE "M."

CAMPAIGN IDENTIFICATION LABEL

EACH VEHICLE CORRECTED IN ACCORDANCE WITH THE INSTRUCTIONS OUTLINED IN THIS PRODUCT CAMPAIGN BULLETIN WILL REQUIRE A "CAMPAIGN IDENTIFICATION LABEL." EACH LABEL PROVIDES A SPACE TO INCLUDE THE CAMPAIGN NUMBER AND FIVE (5) DIGIT DEALER CODE OF THE DEALER PERFORMING THE CAMPAIGN SERVICE. THIS INFORMATION MAY BE INSERTED WITH A TYPEWRITER OR BALL POINT PEN.

EACH "CAMPAIGN IDENTIFICATION LABEL" IS TO BE LOCATED ON THE RADIATOR CORE SUPPORT IN AN AREA WHICH WILL BE VISIBLE WHEN THE VEHICLE IS BROUGHT IN FOR PERIODIC SERVICING BY THE OWNER.

APPLY "CAMPAIGN IDENTIFICATION LABEL" ONLY ON A CLEAN, DRY SURFACE.

ADMINISTRATIVE PROCEDURE

PROCEDURES COVERING THIS CAMPAIGN ARE OUTLINED IN SECTION V OF YOUR DEALERSHIP'S "GMC TRUCK WARRANTY CLAIMS PROCESSING MANUAL" #P9119.

DEAR GM BUS OWNER:

THIS NOTICE IS SENT TO YOU IN ACCORDANCE WITH THE REQUIREMENTS OF THE NATIONAL TRAFFIC AND MOTOR VEHICLE SAFETY ACT.

GENERAL MOTORS HAS DETERMINED THAT A DEFECT, WHICH RELATES TO MOTOR VEHICLE SAFETY, EXISTS IN CERTAIN 1993 GMC TRUCK OR CHEVROLET B7 SCHOOL BUS CHASSIS EQUIPPED WITH HYDRAULIC BRAKES. A CONDITION EXISTS WHERE THE BRAKE PEDAL PUSH ROD COULD BECOME DISENGAGED FROM THE BRAKE BOOSTER RESULTING IN LOSS OF BRAKING CAPABILITY. ALTHOUGH THE BUS CAN STILL BE STOPPED WITH THE PARK BRAKE, LOSS OF SERVICE BRAKES AT A TIME WHEN MINIMUM STOPPING DISTANCE IS REQUIRED COULD RESULT IN A VEHICLE CRASH WITHOUT PRIOR WARNING.

TO CORRECT THIS CONDITION, YOUR GM TOPKICK OR KODIAK MEDIUM DUTY TRUCK DEALER WILL INSPECT FOR PROPER BRAKE PEDAL TRAVEL AND INSTALL A BRAKE PEDAL RETURN STOP TO PREVENT POSSIBLE PUSH ROD DISENGAGEMENT. THIS SERVICE WILL BE PERFORMED FOR YOU AT NO CHARGE.

INSTRUCTIONS FOR PERFORMING THIS SERVICE HAVE BEEN SENT TO YOUR GM TOPKICK OR KODIAK MEDIUM DUTY TRUCK DEALER. PLEASE CONTACT YOUR DEALER TO ARRANGE A SERVICE DATE. PARTS WILL BE AVAILABLE FOR SHIPMENT TO DEALERS ON OCTOBER 18, 1993. THE LABOR TIME NECESSARY TO PERFORM THIS CORRECTION WILL RANGE FROM APPROXIMATELY 1/2 TO 2 HOURS . PLEASE ASK YOUR DEALER HOW MUCH ADDITIONAL TIME WILL BE NEEDED TO PROCESS YOUR VEHICLE.

YOUR GM MEDIUM DUTY TRUCK DEALER IS BEST EQUIPPED TO PROVIDE SERVICE TO ENSURE YOUR VEHICLE IS CORRECTED AS PROMPTLY AS POSSIBLE. HOWEVER, IF YOU TAKE YOUR VEHICLE TO YOUR DEALER ON THE AGREED SERVICE DATE AND THEY DO NOT SERVICE THIS CONDITION ON THAT DATE OR WITHIN FIVE DAYS, WE RECOMMEND YOU CONTACT GMC TRUCK CONSUMER RELATIONS BY TELEPHONE. CONSUMER RELATIONS WILL ASSIST YOU AND YOUR DEALER IN GETTING YOUR VEHICLE CORRECTED. THE TELEPHONE NUMBER OF THE CONSUMER RELATIONS OFFICE IS LISTED IN YOUR WARRANTY AND OWNER ASSISTANCE INFORMATION MANUAL.

AFTER CONTACTING YOUR DEALER AND GMC TRUCK DIVISION, IF YOU ARE STILL NOT SATISFIED THAT WE HAVE DONE OUR BEST TO REMEDY THIS CONDITION WITHOUT CHARGE WITHIN A REASONABLE TIME, YOU MAY WISH TO WRITE THE ADMINISTRATOR, NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, 400 SEVENTH STREET, S.W., WASHINGTON, D.C., 20590, OR CALL 800-424-9393 (WASHINGTON, D.C. RESIDENTS USE 366-0123).

THE ENCLOSED POSTAGE PAID OWNER REPLY CARD IDENTIFIES YOUR VEHICLE. PRESENTATION OF THIS CARD TO YOUR DEALER WILL ASSIST IN MAKING THE NECESSARY CORRECTION TO YOUR VEHICLE IN THE SHORTEST POSSIBLE TIME. IF YOU HAVE SOLD OR TRADED YOUR VEHICLE, PLEASE FURNISH US COMPLETE NAME AND ADDRESS OF THE PERSON YOU SOLD OR TRADED YOUR VEHICLE TO AND RETURN THE CARD TO US.

WE ARE SORRY TO CAUSE YOU THIS INCONVENIENCE; HOWEVER, WE HAVE TAKEN THIS ACTION IN THE INTEREST OF YOUR SAFETY AND CONTINUED SATISFACTION WITH OUR PRODUCT.

GMC TRUCK DIVISION GENERAL MOTORS CORPORATION

93C17 ENCLOSURE

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.