A/T - Shudder/Vibration Upon Acceleration
Article No.92-26A-2
12/16/92
^ VIBRATION - "SHUDDER" UNDER LIGHT OR MODERATE ACCELERATION, ABOVE 35 M.P.H. (55 KM/H) - AXODE TRANSAXLE IN 3RD OR 4TH GEAR
^ TRANSAXLE - AXODE - "SHUDDER" OR "VIBRATION" UNDER LIGHT TO MODERATE ACCELERATION ABOVE 35 M.P.H. 55 KM/H) IN 3RD AND 4TH GEAR
LINCOLN-MERCURY:
1991 CONTINENTAL
ISSUE:
A "shudder" or "vibration" under light to moderate acceleration above 35 M.P.H. (55 km/h) may be caused by the transaxle torque converter clutch. This condition is normally noticed on high mileage vehicles, when the transaxle fluid is cold, with the torque converter clutch engaged and the vehicle under light load.
ACTION:
Test drive the vehicle, confirm shudder or vibration, replace EEC IV processor and transaxle fluid if problem is confirmed. Refer to the following procedure for diagnosis and service details.
DIAGNOSIS PROCEDURE
Test drive the vehicle after the vehicle has cooled for at least four hours and determine if the vehicle shudder or vibration is at speeds above 35 m.p.h. (55 km/h) during light acceleration.
1. Accelerate the vehicle to approximately 45 m.p.h. (72 km/h) until the 3-4 shift occurs and then slow to 41 m.p.h. (66 km/h)
2. Lightly accelerate up to a speed between 44 m.p.h. and 50 m.p.h. (71 and 80 km/h).
If shudder or vibration is noticed, replace the EEC IV processor with a service processor. Also it will be necessary to change the transaxle fluid as outlined in the following service procedure.
NOTE:
WHEN PERFORMING THE FLUID CHANGE AND THE LOWER PAN IS REMOVED, INSTALL THE NEW DESIGN CROSSOVER REAR LUBE TUBE AND DIFFERENTIAL/SPEEDO LUBE TUBE. REFER TO TSB 92-9-7 FOR DETAILS.
TRANSAXLE FLUID CHANGE PROCEDURE
1. Remove lower transaxle pan, clean and reinstall with a new gasket.
2. Loosen hose clamp from top auxiliary cooler fitting and remove the hose. Install approximately 2 feet of 5/16" I.D. hose over the auxiliary cooler fitting and put the opposite end into a large drain pan.
3. Add 10 quarts (8.5 litres) of Mercon fluid into transaxle through fill tube.
4. Start engine with transaxle in park. Run the engine between idle and 1500 r.p.m. for approximately 4 minutes until transaxle fluid is no longer being pumped out of hose.
CAUTION:
SHUT ENGINE OFF AS SOON AS THE FLUID HAS STOPPED BEING PUMPED OUT, TO PREVENT DAMAGE TO THE TRANSAXLE.
5. Reattach the auxiliary cooler hose and tighten the hose clamp.
6. Add 2-1/2 quarts (2.1 litres) of Mercon fluid to the transaxle through the fill tube. Restart the engine. Check and adjust transmission fluid to proper level (cross hatched area of dipstick at normal operating temperature).
CAUTION:
ADD FLUID IN 1/2 PINT (1/2 LITRE) INCREMENTS AFTER ADDING THE 2-1/2 QUARTS (2.1 LITRES). DO NOT OVERFILL! IF FLUID LEVEL IS ABOVE CROSS HATCHED AREA OF DIPSTICK, FLUID MUST BE REMOVED BY DISCONNECTING COOLER LINE.
7. Test drive the vehicle after changing the processor and transaxle fluid to verify that the concern has been corrected.
NOTE:
THE SHUDDER AT LIGHT ACCELERATION SHOULD BE CORRECTED BUT A SLIGHT SHUDDER MAY STILL BE NOTICEABLE WHEN THE CONVERTER CLUTCH ENGAGES (CONVERTER NORMALLY ENGAGES AFTER THE 2-3 SHIFT AT APPROXIMATELY 36-40 M.P.H., 58-64 KM/H). THIS ENGAGEMENT SHUDDER WILL NORMALLY GO AWAY AFTER THE VEHICLE HAS BEEN DRIVEN ABOUT 50 MILES.
Obtain an Authorized Modifications Decal and list the date, dealer number, and summary of alterations performed. Select a prominent place adjacent to the Vehicle Emission Control Information Decal suitable for installing the Authorized Modifications Decal. Clean the area, install the decal, and cover it with a clear plastic decal shield.
Part number/name chart
OTHER APPLICABLE ARTICLES: NONE
SUPERSEDES: 92-20-6
WARRANTY STATUS:
Eligible Under Bumper To Bumper Warranty Coverage
OPERATION DESCRIPTION TIME
926AO2A Road Test /Replace 2.0 Hrs.
Processor/Change Transaxle Fluid
DEALER CODING
BASIC PART NO. CONDITION CODE
12A650 46
OASIS CODES:
501000, 504000, 597997, 703300