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Differential - Chatter On Turns

Article No.
96-12-9

06/03/96

^ NOISE - "CHATTER" DURING TIGHT TURNS OR TURNS AFTER AN EXTENDED PERIOD OF HIGHWAY DRIVING - TRACTION-LOK DIFFERENTIAL - 7.5 AND 8.8 INCH RING GEAR REAR AXLES

^ AXLE - NEW SERVICE KIT AVAILABLE FOR TRACTION-LOK DIFFERENTIAL - 7.5 AND 8.8 INCH RING GEAR

^ AXLE - TRACTION-LOK DIFFERENTIAL - 7.5 AND 8.8 INCH RING GEAR - "CHATTER" NOISE DURING TIGHT TURNS OR TURNS AFTER AN EXTENDED PERIOD OF HIGHWAY DRIVING

FORD:
1989-96 CROWN VICTORIA, MUSTANG, THUNDERBIRD

LINCOLN-MERCURY:
1989-96 COUGAR, GRAND MARQUIS, TOWN CAR

LIGHT TRUCK:
1989-96 AEROSTAR, BRONCO, E-150, RANGER 1989-97 F-150
1991-96 EXPLORER

ISSUE:
A "chatter" noise can be felt and/or heard during tight turns or turns after an extended period of highway driving. This is due to insufficient specified friction modifier, or over-shimming of the clutch packs within Traction-Lok differentials.

ACTION:
Install revised Clutch Pack Replacement Kit (F5ZZ-4947-BA for 7.5" ring gear and F5AZ-4947-BA for 8.8" ring gear), with improved friction material, in the differential after confirming the "chatter" concern with a road test of the vehicle. Refer to the Instruction Sheet within the kit for details.

NOTE:
THE CLUTCH PACK REPLACEMENT KIT INCLUDES SELECTED SHIMS. IT WILL NOT REQUIRE THE ORDERING OF INDIVIDUAL SHIMS BASED UPON TEARDOWN MEASUREMENTS.

REAR AXLE ASSEMBLY IDENTIFICATION

See metal Service Identification tag for rear axle ring gear size and differential type. The identification tag is attached to the rear axle cover by means of a cover bolt.

The Clutch Pack Replacement kit (F5ZZ-4947-BA) for the 7.5" ring gear traction-lok rear axle contains the following:

^ Two (2) Clutch Packs

^ One (1) Pinion Shaft Lockbolt

^ One (1) 4 oz. bottle of Friction Modifier

^ Two (2) Shims - 0.025" thick

^ Two (2) Shims - 0.030" thick

^ Two (2) Shims - 0.035" thick

^ Two (2) Shims - 0.040" thick

^ Two (2) Shims - 0.045" thick

^ One (1) Instruction Sheet (I.S. # 7145)

The Clutch Pack Replacement Kit (F5AZ-4947-BA) for the 8.8" ring gear traction-lok rear axle contains the following:

^ Two (2) Clutch Packs

^ One (1) Pinion Shaft Lockbolt

^ One (1) 4 oz. bottle of Friction Modifier

^ Two (2) Shims - 0.025" thick

^ Two (2) Shims - 0.030" thick

^ Two (2) Shims - 0.035" thick

^ Two (2) Shims - 0.040" thick

^ Two (2) Shims - 0.045" thick

^ One (1) Instruction Sheet (I.S. # 7146)





Parts Block

OTHER APPLICABLE ARTICLES: NONE

WARRANTY STATUS: Eligible Under The Provisions Of Bumper To Bumper Warranty Coverage For 1992-96 Vehicles And Basic Warranty Coverage For All Other Vehicles

OPERATION DESCRIPTION TIME

961209A Replace Traction-Lok 1.4 Hrs.
Differential Clutch Packs -
Crown Victoria/Grand
Marquis, Mustang, Town
Car, E/F-150, Bronco,
Aerostar, Explorer, Ranger

961209B Replace Traction-Lok 2.9 Hrs.
Differential Clutch Packs -
Thunderbird/Cougar

DEALER CODING
CONDITION
BASIC PART NO. CODE
4001 56

OASIS CODES: 509000, 597997, 702200, 702300