CHUGGLE AT 36 MPH & ABOVE WITH TORQUE CONVERTER CLUTCH. Pontiac Bonneville 1994

REVISION: 07/20/94

THIS BULLETIN REVISES THE APPLICABLE MODEL YEARS TO INCLUDE 1994 AND PROVIDES 1994 PART NUMBER INFORMATION. PLEASE DISCARD BULLETIN 376517 (GROUP REFERENCE 6E - ENGINE FUEL & EMISSION). ----------------------------------------------------------------------

SUBJECT: CHUGGLE AT 36 MPH AND ABOVE WITH TORQUE CONVERTER CLUTCH ENGAGED (INSTALL NEW MEM-CAL)

MODELS: 1993-94 BUICK LESABRE, PARK AVENUE AND REGAL 1993-94 CHEVROLET LUMINA APV 1993-94 OLDSMOBILE 88 ROYALE, 98 REGENCY AND SILHOUETTE 1993-94 PONTIAC BONNEVILLE AND TRANS SPORT WITH 3800 ENGINE (VIN L - RPO L27)

CONDITION:

SOME OWNERS MAY EXPERIENCE A CONDITION DESCRIBED AS A "MISS," "SKIP," "CHUGGLE," "HESITATION," OR "FISH BITE" SENSATION WHILE DRIVING THE VEHICLE AT 36 MPH AND ABOVE.

CAUSE:

WITH THE TCC ENGAGED, ANY POWERTRAIN OR VEHICLE ROTATING DISTURBANCE IS TRANSMITTED TO THE PASSENGER COMPARTMENT. REFER TO NOTE 3 UNDER THE HEADING "CORRECTION."

CORRECTION:

IF THE TECHNICIAN DETERMINES NO OTHER CONDITIONS ARE CAUSING THE CONCERN, AS OUTLINED IN SECTION 6E3-B IN THE APPROPRIATE SERVICE MANUAL, A SERVICE MEM-CAL IS AVAILABLE TO ONLY RAISE THE THIRD GEAR TCC LOCK FROM 36 TO 50 MPH AND FOURTH GEAR TCC LOCK FROM 45 TO 54 MPH. NO OTHER DRIVEABILITY ISSUES ARE ADDRESSED WITH THIS MEM-CAL.

NOTE 1 THE REVISED MEM-CALS ARE NOT CONSIDERED A 100 PERCENT CURE, HOWEVER, MOST CUSTOMERS DO NOT PERCEIVE THE "CHUGGLE" OR "FISH BITE" SENSATION WITH THE HIGHER TCC LOCK UP SPEEDS.

NOTE 2 THE REVISED MEM-CALS MAY ADVERSELY AFFECT FUEL ECONOMY (USUALLY LESS THAN ONE MPG DEPENDING ON INDIVIDUAL DRIVING HABITS). BE SURE TO ADVISE THE VEHICLE OWNER OF THIS FACT.

NOTE 3 CHUGGLE MAY ALSO BE CAUSED BY OTHER CONDITIONS, FOR EXAMPLE, OUT-OF-BALANCE TIRES, OUT-OF-ROUND TIRES, ENGINE MISS DUE TO IGNITION RELATED COMPONENTS OR A MECHANICAL FAILURE, A/C COMPRESSOR CYCLING, TCC MALFUNCTIONS CAUSING EXCESSIVE SLIP VALUES AS MEASURED WITH A TECH 1, AND SPECIFIC ROAD SURFACE CONDITIONS.

SERVICE INFORMATION:

USE THE PROCEDURE IN SECTION 6E3 IN THE SERVICE MANUAL FOR MEM-CAL REPLACEMENT. THERE HAVE BEEN NO CHANGES IN THE REMOVAL AND INSTALLATION PROCEDURE.

PARTS INFORMATION:

1993 MODEL YEAR APPLICATIONS

SERVICE B/C MEM-CAL MEM-CAL CODE ID AXLE EMIS. MARKETING DIVISIONS ------- ---- ------- ---- ----- ------------------- "CB" CHUGGLE MEM-CAL - BUICK PARK AVENUE AND OLDS 98 REGENCY -------------------- 16202846 BKTH 2874 2.84 FED. BUICK, OLDSMOBILE 16202856 BKTJ 2884 2.84 CALIF. BUICK, OLDSMOBILE 16202861 BKTK 2894 3.06 FED. BUICK, OLDSMOBILE 16202865 BKTL 2904 3.06 CALIF. BUICK, OLDSMOBILE 16202868 BKTM 2914 3.06/16" WHEEL FED. OLDSMOBILE 16202872 BKTN 2924 3.06/16" WHEEL CALIF. OLDSMOBILE

"HB" CHUGGLE MEM-CAL - BUICK LESABRE, OLDS 88 ROYALE, PONT. BONNEVILLE -------------------- 16202880 BKTP 2934 2.84 FED. BUICK, OLDS, PONTIAC 16202883 BKTR 2944 2.84 CALIF. BUICK, OLDS, PONTIAC 16202887 BKTS 2954 3.06 FED. BUICK, OLDSMOBILE 16202891 BKTT 2964 3.06 CALIF. BUICK, OLDSMOBILE 16202895 BKTU 2974 3.06/16" WHEEL FED. OLDSMOBILE, PONTIAC 16202898 BKTW 2984 3.06/16" WHEEL CALIF. OLDSMOBILE, PONTIAC

"WB" CHUGGLE MEM-CAL - BUICK REGAL

16203286 BKXF 3254 3.06 FED. BUICK 16203289 BKXH 3264 3.06 CALIF. BUICK

"UB" CHUGGLE MEM-CAL - CHEVROLET LUMINA APV, OLDSMOBILE SILHOUETTE, -------------------- PONTIAC TRANS SPORT 16203670 BKXY 3644 3.06 NW CHEV., OLDS, PONTIAC

1994 MODEL YEAR APPLICATIONS

"CB" CHUGGLE MEM-CAL - BUICK PARK AVENUE, OLDSMOBILE 98 REGENCY

16202825 BKTB 2834 2.84 NW BUICK, OLDSMOBILE 16202816 BKSZ 2814 3.06 NW BUICK, OLDSMOBILE

"HB" CHUGGLE MEM-CAL - BUICK LESABRE, OLDSMOBILE 88 ROYALE, PONTIAC -------------------- BONNEVILLE SE 16202842 BKTF 2864 2.84 NW BUICK, OLDS, PONTIAC 16202828 BKTC 2844 3.06 NW BUICK, OLDS, PONTIAC 16202832 BKTD 2854 3.06/16" WHEEL NW PONTIAC

"WB" CHUGGLE MEM-CAL - BUICK REGAL

16203293 BKXJ 3274 3.06 NW BUICK

"UB" CHUGGLE MEM-CAL - CHEVROLET LUMINA APV, OLDS SILHOUETTE, PONTIAC -------------------- TRANS SPORT 16203681 BKYA 3664 3.06 NW CHEVROLET, OLDS, PONTIAC

PARTS FOR 1993 APPLICATIONS ARE CURRENTLY AVAILABLE FROM GMSPO. PARTS FOR 1994 APPLICATIONS ARE EXPECTED TO BE AVAILABLE FROM GMSPO ON JULY 11, 1994.

WARRANTY INFORMATION:

LABOR OPERATION: T0500 LABOR TIME: 0.6 HOURS

FIGURES: 0

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.