SERVICE MANUAL UPDATE-SEC. 7A 2B AUTO TRANSAXLE UNIT REPAIR

SUBJECT: SERVICE MANUAL UPDATE - SECTION 7A2B - JF403E AUTOMATIC TRANSAXLE UNIT REPAIR

VEHICLES AFFECTED: 1991-93 GEO STORM

APPLICATION:

----------- 1991-93 Geo Storm

This bulletin updates service information in JF403E Automatic Transaxle - Unit Repair (Section 7A2B) of the 1991-93 Geo Storm Service Manuals (ST371-91, ST371-92 and ST371-93, respectively).

REVERSE CLUTCH

Measure

Clearance between the reverse clutch retaining plate and the snap ring using a feeler gage. Standard clearance is 0.5 to 1.2 mm (0.020 to 0.047-inch). If the clearance is outside these parameters, replace the retaining plate with the appropriate size plate.

HIGH CLUTCH

Measure

Clearance between the high clutch retaining plate and the snap ring using a feeler gage. The standard clearance is 1.8 to 2.8 mm (0.071 to 0.110-inch). If the clearance is outside of these parameters, replace the retaining plate with an appropriate size plate.

FORWARD CLUTCH AND OVERRUN CLUTCH

Measure

Clearance between the overrun clutch retaining plate and the over- run clutch snap ring using a feeler gage. The standard clearance is 1.0 to 2.0 mm (0.039 to 0.079-inch). If the clearance is outside of these parameter's, replace the overrun clutch retaining plate with an appropriate size plate.

Clearance between the forward clutch retaining plate and the forward clutch snap ring using a feeler gage. The standard clearance is 0.45 to 2.25 mm (0.018 to 0.099-inch). If the clearance is outside of these parameters, replace the forward clutch retaining plate with an appropriate size plate.

LOW AND REVERSE BRAKE

Measure

Clearance between the low-reverse clutch retaining plate and the spacer using a feeler gage. The standard clearance is 1.1 to 2.9 mm (0.043 to 0.114-inch). If the clearance is outside of these parameters, replace the retaining plate with an appropriate size plate.

DIFFERENTIAL CASE

Measure

Differential gear backlash between the side gear and the pinion gear using a J 8001 dial indicator. If the backlash is greater than 0.3 mm (0.19-inch) replace the side gear thrust washers with an appropriate size washer.

0.765 mm (0.0301-inch) 0.820 mm (0.0323-inch) 0.880 mm (0.0346-inch) 0.940 mm (0.0370-inch)

OIL PUMP - TO - HIGH CLUTCH SHIM ADJUSTMENT

Step number 3 on Page 7A1-2-40 of the 1991 Geo Storm Service Manual and step number 3 on Page 7A2B-51 of the 1992 and 1993 Geo Storm Service Manuals should read:

3. Place the J 35284-1 bridge and leg assembly, the J 35284-1 9 bridge extension with J35284-4 gage cylinder and the J35284-32 high clutch gage pin on the transaxle case.

THE GASKET SHOULD NOT BE INSTALLED WHEN PERFORMING THIS ADJUSTMENT.

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.