A/T - Squeaking or Chirping Sound During 2 to 3 Upshift

BULLETIN NO. 466

DATE: AUGUST, 1994

03
16

SUBJECT:
UPSHIFT NOISE IN AUTOMATIC TRANSMISSION

MODELS:
ALL 405 VEHICLES EQUIPPED WITH ZF 4HP14

COMPLAINT:

The automatic transmission may emit a "squeaking" or "chirping" sound when shifting from second to third gear. This noise usually occurs under light to moderate throttle pressure and may be more prevalent after a transmission service or replacement. It does not indicate a transmission failure or impending failure, however it may be a source of customer complaint.

CORRECTION:

Use a transmission fluid additive called LUBEGARD Automatic Transmission Fluid Supplement which can be obtained from the National Parts Department under Part Number 9735.C2.

REPAIR:
- Inspect the condition of the fluid. If there is any sign of burning or contamination, the transmission should be serviced.
- Perform a brief road test to ensure proper transmission operation (other than the subject noise).
- Adjust kick-down cable if necessary, see Service Bulletin Number 415, class 3, dated April, 1991 for details.
- Add 150 ml (5.0 fl.oz.) of LUBEGARD to the transmission.
- Return the vehicle to the customer and allow them to drive the vehicle under normal conditions for 200 to 300 miles, at which time the noise should subside.

SERVICE ACTION:

LUBEGARD should be added whenever it is necessary to service or replace an automatic transmission. For warranty repairs, the expendable fluid allowance will be adjusted accordingly.