A/T - Harsh 1-2 Upshift When Hot During Acceleration

Bulletin 86-7125-5B

Date Apr. '87

Ref. No. 86-124B-7125

Corp. Ref. No. 677102R
SUBJECT: HARSH 1-2 UPSHIFT WHEN HOT DURING MEDIUM TO HARD ACCELERATION

MODELS AFFECTED: 1986 SKYHAWKS, SKYLARKS, SOMERSETS AND CENTURYS EQUIPPED WITH THM 125C TRANSAXLES
NOTE: This bulletin supersedes 86-7125-5A which was published without Transaxle Model PNC. Please discard bulletin 86-7125-5A and replace it with this one.

FIGURE 1 - THM 125/125C TRANSAXLE I.D. NAMEPLATE YPSILANTI, MICHIGAN:

A 1986 THM 125C transaxle may experience a harsh 1-2 upshift when hot during medium to hard throttle acceleration. Refer to Figure 1 for transaxle identification information and to chart below for models.

FIGURE 2:

When servicing this condition on a THM 125C transaxle built between the serial numbers listed below, remove the spacer plate and measure the diameter of the 1-2 accumulator feedback orifice (Refer to Figure 2 for location). If the hole is 1.02 mm (0.040"), replace the spacer plate with the indicated service spacer plate, which has a larger (3.18 mm/0.125") 1-2 accumulator feedback orifice.
SERIAL NUMBER SERIAL NUMBER SPACER PLATE
MODEL START END PART NUMBER

BAC 4482 6468 8660575
BDC 2137 2289 8660575
BPC 52519 57074 8660575
CAC 8054 8280 8660581
CBC 127346 128483 8660581
CCC 1914 2059 8660581
CMC 1283 11286 8660581
PHC 10949 12483 8660552
PKC 13015 14585 8660552
PRC 35775 39656 8660552
PNC 147386 162750 8660552

Refer to the appropriate service manual for removal and installation procedures.