F 250 4WD Pickup V8-5.4L SOHC VIN L (1999)
Planetary Gears: Customer Interest
A/T - 4R70W Clunk Noise on 2nd to 1st Gear Downshift
Article No.
01-13-7
07/09/01
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NOISE - "CLUNK" NOISE HEARD ON 2-1
DOWNSHIFT VEHICLES EQUIPPED WITH 4R70W
AUTOMATIC TRANSMISSION
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TRANSMISSION - 4R70W - "CLUNK" NOISE HEARD
FROM TRANSMISSION ON 2-1 DOWNSHIFT
FORD:
1999-2001 CROWN VICTORIA, MUSTANG
1999 F-250 LD
1999-2001 E SERIES, EXPEDITION, EXPLORER, F-150
LINCOLN:
1999-2001 TOWN CAR
MERCURY:
1999-2001 GRAND MARQUIS, MOUNTAINEER
ISSUE
Some vehicles equipped with a 4R70W automatic transmission may exhibit a "clunk" noise during the 2-1 downshift event. The "clunk" noise will be
consistent in nature, and will occur during most 2-1 downshifts. This may be caused by a Planet Support Spring that is out of position.
ACTION
Check for the correct installation of the Planet Support Spring. If the spring is not installed correctly, the Planetary Gear Support will make contact with
the transmission case during the 2-1 downshift, causing the "clunk" noise. Refer to the following Service Procedure for details.
SERVICE PROCEDURE
NOTE
THE "CLUNK" NOISE DESCRIBED IN THIS ARTICLE SHOULD NOT BE CONFUSED WITH HARSH/ROUGH 2-1 DOWNSHIFT
CONDITION. IF A HARSH/ROUGH 2-1 SHIFT CONDITION IS PRESENT, FOLLOW NORMAL WORKSHOP MANUAL DIAGNOSTIC
PROCEDURES.
1.
Use Chassis Ears (Rotunda number 107-R2102 or equivalent) to verify the "clunk" noise is originating from the transmission during the 2-1
downshift event.
NOTE
IF THE NOISE IS NOT ORIGINATING FROM THE TRANSMISSION DO NOT CONTINUE WITH THIS SERVICE PROCEDURE. USE THE
CHASSIS EARS TO HELP PINPOINT THE ORIGIN OF THE NOISE, THEN DIAGNOSE AND REPAIR AS NEEDED.
2.
Raise and support vehicle. Refer to Workshop Manual Section 100-02.
3.
Check for correct torque on the following chassis & drivetrain components:
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Driveshaft to Pinion Flange fasteners
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Upper and Lower Control Arm fasteners (car applications)
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Rear Leaf Spring Fasteners (truck applications)
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Rear Shock Absorber fasteners
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Transmission Mount and Crossmember fasteners
4.
If any discrepancies are found, correct and test drive vehicle to verify repair. If condition is not corrected, continue to Step 5.