TRANSAXLE BRG. WHINE AUDIBLE IN 1ST,2ND, & 3RD GEAR

Subject: TRANSAXLE BEARING WHINE AUDIBLE IN 1ST, 2ND, AND 3RD GEAR

Model and Year: 1991-93 LUMINA AND 1991-93 LUMINA APV WITH 4T60/4T60-E AUTOMATIC TRANSMISSION

Some vehicles equipped with a HYDRA-MATIC 4T60 (RPO ME9) or 4T60-E (RPO M13) transaxle built on or before June 23, 1993 (Julian Date 174), may exhibit a transaxle bearing whine that is audible in 1 st, 2nd, and 3rd gear. The whine is most audible on the "driver's" side of the vehicle while in 2nd gear during a light throttle acceleration.

IMPORTANT: This bearing whine cannot be heard in "Park" or "Neutral."

CAUSE: (Figure 1) ----- The Bearing Assembly, 4th Channel Plate Hub/Channel Plate" (503/ 431) may have been improperly installed causing the needle bearings to leave indentation marks on the bearing race.

CORRECTION:

---------- Replace the "Bearing Assembly, 4th Channel Plate Hub/ Channel Plate" (503/431) located on the "Channel Plate Assembly" (404/401).

PART INFORMATION:

Part number for the"Bearing Assembly, 4th Channel Plate Hub/ Channel Plate" is the same for the 4T60 and 4T60- E transaxle.

PART NUMBER DESCRIPTION: ----------- ----------- 8656393 Bearing Assembly, 4th Channel Plate Hub/Channel Plate

Parts are currently available from GMSPO.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.