Lumina V6-191 3.1L (1990)
TO:
ALL CHEVROLET DEALERS
BULLETIN COVERS:
A vehicle equipped with a 1987-91 HYDRA-MATIC 4T60 transaxle may exhibit no reverse, slipping in reverse and/or repeat reverse band distress. This
may be caused by interference between the reverse band apply bracket and the case. The suspected transaxle cases have an additional wall thickness in
the area where the reverse band apply pin engages the apply bracket. The band may never fully apply or release once caught and will distress the fiber
liner material across all straps.
SERVICE PROCEDURE:
If the transaxle exhibits any of the symptoms discussed in this bulletin, inspect the case die number as shown in Figure 1 and the transaxle Julian Date. If
the case die number matches the suspect numbers and the transaxle Julian Date is after the dates listed, disassemble the transaxle and check the case
spline number (Figure 2) (located deep inside the barrel of the case next to the right axle seal). If it is listed below, replace the case. If the transaxle is not
a suspect unit, then refer to the Automatic Transaxle Diagnosis section of the Service Manual for repair procedures.
LABOR TIME INFORMATION:
Labor Operation:
K7800 - Case, Transaxle - Replace
See applicable Labor Time Guide for Labor Hours.
SERVICE PARTS INFORMATION:
Part are currently available from GMSPO.
SERVICE MANUAL REFERENCE:
Refer to the appropriate Service Manual for proper procedures.
