DIAGNOSIS INFORMATION FROM EXCHANGE PROGRAM

1987-88 FIRENZA, 1988 CUTLASS CALAIS AND 1988 CUTLASS SUPREME EQUIPPED WITH MODELS/YEARS: HM-282/HMD-5TM40 5-SPEED MANUAL TRANSAXLE (RPO MG2)

BULLETIN COVERS: (Figure 1) ---------------- Diagnosis information on 1986-1 /2 through 1988 vehicle applications equipped with a HM-282 five-speed manual transaxle. This information was gained from the expired exchange program disassembly analysis of returned transaxles. Before repairs are attempted, refer to the following diagnostic chart as a guide.

SERVICE ACTION:

Preliminary Diagnosis Procedure:

- Insure correct fluid level and proper type. - Insure that the clutch is working properly (spin-down time and lost motion). - Insure that all engine and transaxle mounts are tight.

SERVICE PARTS INFORMATION:

Parts are currently available from GMSPO.

SERVICE MANUAL REFERENCE:

Information in this bulletin is intended to supplement the HM-282 Section of your Service Manual.

1987 and 1988 HM-282 DIAGNOSTIC CHART

NOTE: For all figure references, refer to the HM-282 on-car service section 7B3 or the HM-282 Unit Repair Section 7B3A of the 1988 Service Manual.

1987 & 1988 HM-282 DIAGNOSTIC CHART

NOTE: FOR ALL FIGURE REFERENCES, REFER TO THE HM-282 ON-CAR UNIT REPAIR SECTION 7B3 OR THE HM-282 UNIT REPAIR SECTION 7B3A oF THE 1988 SERVICE MANUAL

CONDITION System INSPECT COMPONENT FOR CAUSE (General Description) ----------------------------------------------------------------------------- SHIFTING -------- Excessive Shift Effort - Proper Type Of Fluid - Improper fluid or level, Effort Required And Level Of Fluid USE G.M. P/N 12345349 In All Forward Gears (automatic transmission (Engine Running) fluid or engine oil does not work well with synchronizers resulting in increased shift effort). Refer To Bulletins:

Oldsmobile 88-T-37

(Clutch Spin-Down Time - Clutch - Improper spin-down time. OK, Lubricant Type And To check clutch spin down Level OK) time: 1.Run the engine at normal idle with the transaxle in neutral and the clutch engaged. 2.Disengage the clutch, wait nine seconds and shift the transaxle into reverse. 3.If a grinding noise is heard, refer to the clutch diagnosis section of your Service Manual. --------------------------------------------------------- Into Or Out Of Gear - Shift Cable (Remove Cable - Binding, kinked, worn or (Same Effort With From Transaxle And Test not routed or secured Engine Running Or For Ease Of Movement) correctly. Not) - Shifter Mechanism in Car - Worn or damaged. (Disconnect Cables In Car And Move Shifter To Test For Ease Of Movement) - Shift Lever Nut (137) - Loose, allowing the shift lever to bind while shifting. Refer To Bulletins:

Oldsmobile 88-T-68

- Shift Rail(s) (184), (190) - Binding shaft/rails. And (197) Of Affected Gear - Shift Rail Bushing(s) (99) - Worn/damaged binding And (176) Of Affected rails. Gear ------------------------------------------------------------ Reverse Gear - Reverse Idler Gear (103), - Gear teeth mating and Input Shaft (17) And damaged, mutilated (mush- Reverse Gear (26) roomed). (Customer hitting reverse on 5th to 4th down- shift.) Once damaged/worn parts are replaced, have customer change shift pattern (not round off the 5th to 4th downshift).

- Reverse Lever (153) - Bent (both ears must be in same plane). - Reverse Shift Rail - Binding/worn components. Assembly (180) - Reverse Shift Rail - Worn or missing. Bushing (167)

- Engine Idle Speed - Too high causing excessive effort. (Also 1st gear.) ------------------------------------------------------------ Hard To Shift - Select Cable (Remove - Binding, kinked, worn or Into Shift Gates Cable From Transaxle And not routed or secured (1-2, 3-4 Test For Ease Of correctly. 5-Reverse) Movement) (Side To Side) ------------------------------------------------------------ Hard Shift Into - Cover (140) - Cover installed too deep or 1-2 Gate the top of the cover is not allowing full travel caved in, of the shift shaft (155). ------------------------------------------------------------------------------ EXCESSIVE CLUTCH PEDAL EFFORT ------------ (Early External - Clutch Fork Shaft (165) - Corroded or worn. (Use Release And Inner Clutch Fork service clutch fork shaft Models Only) Bushing (177) On Units with chromed end, G.M. P/N Built Before October 26, 8672937). Also order and 1987. On This Date A replace bushings (not Needle Bearing (217) is included in parts package). Used instead Of Bushing (177)

- Input Shaft Bearing/Sleeve - Worn, gouged and/or cracked Assembly (21) at flange, binding clutch release bearing (22). - Lack of high temperature grease. - Excessive clutch disc dust contaminating grease, causing increased effort.

- Clutch Fork Shaft (165) - Clutch fork parallelism [fork Or (216) fingers not touching release bearing (22) at the same time. This causes the release bearing to bind on the input shaft bearing/sleeve assembly (21)].

- Clutch Fork Shaft - Worn or damaged. Bearings Or Bushings (163), (177) Or (217)

- Refer To Clutch And Slave Cylinder Diagnosis ------------------------------------------------------------ No Shift Into - Fork Retainer Pin (193) - Missing, backed out from 1st And 2nd Gear On Units Built Before vibration. Replace lst/2nd (Lever Will Shift December 11, 1987. On shift rail assembly (190). But No Gear This Date The Fork Pin All service parts have the Engagement) Hole In The Rail (195) Was tighter fork pin rail hole. Made Smaller So The Pin Will Not Back Out ----------------------------------------------------------- No Shift Into 3rd - Fork Retainer Pin (186) - Missing, backed out from And 4th Gear (Lever On Units Built Before vibration. Replace 3rd/4th Will Shift But No November 25, 1987. On shift rail assembly (184). Gear Engagement) This Date The Fork Pin All service parts have the Hole In The Rail (189) Was tighter fork pin rail hole. Made Smaller So The Pin Will Not Back Out ----------------------------------------------------------- No Shift Into 5th - Fork Retainer Pin (197) - Missing, backed out from Gear (Lever Will On Units Built Before vibration. Replace 5th shift Shift But November 25, 1987. On rail assembly (197). All No Gear Engagement) This Date The Fork Pin service parts have the Hole In The Rail (202) tighter fork pin rail hole. Was Made Smaller So The Pin Will Not Back Out

------------------------------------------------------------------------------ HOP OUT ------- Slips Out Of Gear On Acceleration Or Decele- ration (Transaxle Under Load) lst Gear - Thrust Bearing (51) And/ - Missing or worn (allowing too Or Thrust Washer (52) much end play). ----------------------------------------------------------- 1st Gear And/Or - lst/2nd Synchronizer - Damaged or worn spline lock 2nd Gear Sleeve (43) And/Or Hub on hub and/or sleeve. (47) ----------------------------------------------------------- 3rd Gear And/Or - 3rd/4th Synchronizer - Damaged or worn spline lock 4th Gear Sleeve (9) And/Or Hub on hub and/or sleeve. (13) ----------------------------------------------------------- 5th Gear - 5th Synchronizer Sleeve - Damaged or worn spline lock (30) And/Or Reverse on hub and/or sleeve. Gear (26) ----------------------------------------------------------- (Coast ie. Not - Shift Rail(s) Detent - Damaged, worn or missing Acceleration Or Assembly (189), (195), parts. Deceleration) (202), (170) And (171) (Any Gear) Of Affected Gear ------------------------------------------------------------------------------ HARD SHIFTING ------------- Neutral To 1st - 1st Output Gear (49) - Updated for Start of Pro- duction 1988. Changed angle of clutching teeth to help shift (110 deg. to 118 deg.). ----------------------------------------------------------- Hard lst-2nd - Output Gear Shim (87) - Missing or too thin causing too much end play for output shaft (53). ----------------------------------------------------------- 1st And/Or 2nd - 1st And/Or 2nd Blocking - Bronze material transfer to Rings (48) And (41) On speed gear cone(s). Replace Units Built Before speed gear of affected December 11, 1987. gear. All service parts are Changed Manufacturing updated parts. Process To Make Bronze More Durable ----------------------------------------------------------- 3rd, 4th, - 3rd, 4th And/Or 5th - Bronze material transfer to And/Or 5th Blocking Rings (14),(7) speed gear cone(s). Replace And/Or (31) On Units speed gear of affected gear. Built Before December 1, All service parts are updated 1987. Changed Manufac- parts. turing Process To Make Bronze More Durable ----------------------------------------------------------- Hard Shift Into - Reverse Lever (153) - Bent. 5th Gear ----------------------------------------------------------- Unable To Shift - Reverse Shift Rail - Missing parts. Out Of 5th Gear Assembly (180) Especially Gear Disengage Roller (182) ----------------------------------------------------------- Unable To Shift - Snap Ring And Detent - Missing parts. Into Any Gear Plug (209) And (210) ----------------------------------------------------------- Blocked-Out In - Synchronizer Sleeve Of - Replace sleeve of affected Any Forward Gear Affected Gear (9), (43) gear if there is NO bronze And/Or (30) transfer from blocking ring to speed gear cone. Refer to above 1st-2nd and/or 3rd, 4th and 5th. ------------------------------------------------------------------------------ LOCKED-IN GEAR -------------- - Shift Rail Detent - Misassembled or worn parts. Assembly (171), (169), (189),(195),(202) And (183) (This Will Happen After An Overhaul)

- Detent Lever Assembly - Disassembled or severely (145) damaged. ----------------------------------------------------------- Unable To Shift - Reverse Shift Rail - Missing parts. Out Of 5th Gear Assembly (180) Especially Gear Disengage Roller (182) ------------------------------------------------------------------------------ GEAR CLASH/ GRINDS ----------- In All Forward - Proper Type Of Fluid - Improper fluid or level, USE Gears And Level Of Fluid G.M. P/N 12345349 (automatic transmission fluid or engine oil does not work well with synchronizers resulting in gear clash). Refer To Bulletins:

Oldsmobile 88-T-37

(Clutch Spin-DownTime OK, Lubricant Type And Level OK)

1st And/Or 2nd - 1st And/Or 2nd Blocking - Bronze material transfer to Rings (48) And (41) On speed gear cone(s). Replace Units Built Before speed gear of affected gear. December 11, 1987. All service parts are updated Changed Manufacturing parts. Process To Make Bronze More Durable ----------------------------------------------------------- 3rd, 4th And/Or - 3rd, 4th And/Or 5th - Bronze material transfer to 5th Blocking Rings (14), (7) speed gear cone(s). Replace And/Or (31) On Units speed gear of affected gear. Built Before December 1, All service parts are updated 1987. Changed Manu- parts. facturing Process To Make Bronze More Durable ----------------------------------------------------------- In All Forward Gears (Clutch Spin- Down Time OK, - Clutch - Improper spin-down time. Lubricant Type And Level OK) To check clutch spin down time: 1. Run the engine at normal idle with the transaxle in neutral and the clutch engaged. 2. Disengage the clutch, wait nine seconds and shift the transaxle into reverse. 3. If a grinding noise is heard, refer to the clutch diagnosis section of your Service Manual. ------------------------------------------------------------------------------ NOISE ----- Neutral Rattle - Loose Vacuum Line On - Improper running engine (Clutch Engaged) Engine transferring irregular pulses to transaxle gear set, causing rattle. ---------------------------------------------------------- (Will Be Loudest - Disconnected Spark Plug When The Wire Accessories Are On, As When The Air Conditioner - Out Of Tune Engine Compressor is Cycling) - Idle RPM

- Engine Timing

(Will Be More - Slight Rattle Is Normal Noticeable With Because Clutch Disc Does The Window(s) Down) Not Have A Anti-Rattle Device (Will Not Cause A Durability Concern)

- Refer to Clutch Diagnosis

- Input Shaft Bearing/ - Broken flange, rubbing. Sleeve Assembly (21)

- Input Gear Bearing (93) - Damaged or worn bearing.

- Speed Gear Bearing(s) - Damaged or worn bearing. (16) And (5)

- Bearing Races (17) - Damaged or worn races. And (6)

- Input Shaft (17), 3rd - Damaged or worn thrust Input Gear (15), surfaces. 3rd-4th Synchronizer Clutch Hub (13) And 5th Input Gear (3)

- Clutch Release Bearing - Damaged or worn bearing. Assembly (22) ------------------------------------------------------------ Neutral Rattle Noise In All - Clutch And Differential - Cracked, a foreign object Gears (Bearing Housing (20) At The between output shaft and Noise) Output Bearing Race (56) differential (broken speedo Bore signal assembly (172) driven gear shaft, or loose bolt, lever retainer pin or roll pin.

- Output Gear Bearing - Worn or damaged. Replace both (86) bearings (86) and (93) with bearings in Overhaul Kit G.M. P/N 8672918.

- Shift Rail Guide Bolt - Loose, rubbing on gear. (18) ------------------------------------------------------------ Differential - Output Bearing Race - Installed upside down, ring Retainer (178) gear (70) rubbing on retainer because cutout for ring gear is now installed down. ------------------------------------------------------------ (Will Be Noisy - Detent Holder Cover - Not installed flush with bore, With The Car (174) clutch plate rubbing on cover. Moving Or Not Moving) ------------------------------------------------------------ Final Drive - Output Shaft (53) And - Worn or damaged. Noise (64-80 Differential Ring Gear KMH, 40-50 MPH (70) On Units Built Before In 4th Gear) April 15, 1987. On This Date The Gear Tooth Profile Was Changed To Lessen Noise ------------------------------------------------------------------------------ LEAKS ----- - Fluid Level - Overfilled because of improper checking procedure. Fluid level IS NOT CHECKED THROUGH FILL TUBE THAT BOLTS ONTO SIDE OF HOUSING. Refer To Bulletins:

Oldsmobile 87-T-04A

- Fluid Level Indicator - Old style indicator not Assembly (110) And Bore sealing bore. Replace with G.M. P/N 22540197. Refer To Bulletins:

Oldsmobile 88-T-06

(From Clutch Area) Slave Cylinder - Refer To Slave Cylinder Leak Diagnosis

- Input Shaft Bearing/ - Worn or damaged seal. Sleeve Assembly (21) - Worn rollers, allowing input shaft to move more than seal.

- Input Shaft (17) - Damaged surface that mates with seal. - Detent Holder Cover - Damaged. (174) - Reverse Idler Bolt - Loose (94) - Lack of proper sealant.

- Shift Shaft Cover - Reused or damaged. (140) - Missing snap ring (139). ------------------------------------------------------------ Differential - Oil Drive Axle Seal(s) - Worn or damaged seal. Part Of (23) And/Or Equal Drive Housings Axle Extenders Seal ------------------------------------------------------------ (Allowing The - Thrust Side Gear - Worn. Drive Axle To Washer(s) (65) in Move More Than Differential Assembly Axle Seal, Case (61) Causing Leak) - Speedo Signal Assembly - Worn or torn. Seal (220) - Bore damaged. - Debris in seal groove of sensor.

- Speedo Signal Assembly - Internal leak. (172)

- Oil Drain Plug (79) - Loose. - Cross threaded.

- Oil Drain Plug Washer - Worn, damaged or missing. (80)

- Shift Shaft Seal (208) - Worn, damaged or missing.

- Back-up Lamp Switch - Loose. Assembly (219) - Lack of proper sealant. ----------------------------------------------------------- From Side - Transmission Case End - Damaged, warped or lack of With Plate Plate (90) sealant.

- Bolt(s) (91) - Loose or lack of sealant.

- Output Gear Bearing - Too thick, not allowing trans- Retainer Shim (87) axle case end plate (90) to properly seat.

- Bolt (205) - Loose. - Lack of proper sealant. - Cross threaded. ------------------------------------------------------------------------------ BACK-UP LAMPS DO NOT TURN ON -------------- - Back-Up Lamps - Burned out.

- Check Fuse

- Reverse Rail Bushing - Omitted. (98)

- Back-Up Light Wiring - Loose or corroded connections. Circuit

- Back-Up Lamp Switch - Defective. Assembly (219)

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.