PART USAGE REVISION/BOLT SIZE AND FASTENER TIGHTENING SPEC.

SUBJECT: PART USAGE REVISION/BOLT SIZE AND FASTENER TIGHTENING SPEC CHANGE ON ENGINE MOUNT BRACKET

MODELS AFFECTED: 1992-93 GRAND AM MODELS (VINS A/D/3) ENGINE APPLICATIONS: 2.3L (RPOs LGO, LD2, and L40)

CONDITION:

--------- A small number (about 2 percent of total production) of early production 1992 model year 2.3L engines with automatic transaxles were produced with M-10 bolts (13 mm bolt head) to attach the engine mount bracket (upper) to the engine block. When the engine mount bracket bolts are removed, replace them with new bolts (GM P/N 14034683 with Loctite 75, without substitution). The fastener tightening specification is listed below.

Later production 1992 and all 1993 model year 2.3L engines had M-12 bolts to attach the engine mount bracket (upper) to the block and have different tightening specifications than the M-10 bolt. When the engine mount bracket (upper) bolts are removed, replace them with new bolts (bolt GM P/N 22579611, without substitution). Tighten bolts to the specified N.m (lbs. ft.) then rotate the bolt the specified degrees with Torque Angle Meter J-36660.

BOLT BOLT TORQUE SIZE HEAD SIZE PART NUMBER TRANS SPECIFICATION ---- --------- ----------- ----- ------------- M-10 13 mm 14034683 Bolt Auto 30 N.m (41 lbs. ft.) Plus rotate 60 degrees

M-12 15 mm 22579611 Bolt Auto 60 N.m (44 lbs. ft.) Plus rotate 90 degrees

M-12 15 mm 22579611 Bolt Manual 110 N.m (81 lbs. ft.) Plus rotate 90 degrees

Parts are expected to be available on February 8, 1993.

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.