Affected Component: POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE)

Date Published
JUL 31, 2014
NHTSA TSB #
10101682
TSB Document
Summary
"ISSUE: A NOISE WHICH CAN BE DESCRIBED AS A RUBBING/SCRAPPING/DRONE OR IN SOME CASES MAYBE REPORTED AS A VIBRATION IS FOUND TO BE EVIDENT FROM THE LEFT HAND FRONT CORNER OF THE VEHICLE. THE NOISE CAN ALSO BE DESCRIBED AS SIMILAR TO A BRAKE RUBBING OR WHEEL BEARING NOISE AND CAN BE VARIABLE FROM VEHICLE TO VEHICLE. THE ISSUE CAN OCCUR AT DIFFERENT SPEEDS/GEARS AND IN STEADY STATE DRIVING CONDITIONS UP TO 50/60MPH (80/100KM/H), HOWEVER THE NOISE IN MOST CASES IS MORE PROMINENT IN 2ND GEAR COAST DOWN PARTICULARLY AROUND 12MPH (20KM/H). TO CONFIRM, THE NOISE CAN LISTENED TO USING ‘CHASSIS EAR’ FIXED TO FRONT DIFFERENTIAL RH MOUNT. CAUSE: CHORDAL VIBRATION OF THE TRANSFER CASE CHAIN ON COAST/OVERRUN. FITMENT OF THE FRONT DIFFERENTIAL SUPPORT BRACKET MAY ELIMINATE THE NOISE WITHOUT THE NEED TO REPLACE THE COMPLETE TRANSFER BOX ASSEMBLY"